Louwrentius - Hardware

What will you do when AI runs out of money and disappear?

2026-01-23T12:00:00+01:00

All major AI services like ChatGPT or Claude are heavily subsidised by investors. It's not just the initial investment — it's the running costs of these major AI services that are also astronomical.¹

At some point the money will run out. Assuming that Ed Zitron is right about his assessment of the AI market (and he's not alone in his assessment), the current big AI services are not sustainable. And there seems to be no realistic path to profitability.

How are the big AI providers going to make $2 Trillion in the next 4 years?

So what happens when money runs out? When the music stops, will there be any chairs at all?

I see two major scenarios:

The AI services are just shutdown overnight
The AI services are priced according to actual cost + profit

In the first scenario, those who have build their entire workflow on AI support have a serious problem. AI servies as a massive single-point-of-failure. Quite a few very optimistic roadmaps have to be adjusted, I guess.

The second scenario may be effectively identical to the first, as AI services may become so expensive that their usage can't be justified. For no reason I can think of, the company "VMWare" comes to mind, strange isn't it?

As there are open-source models available, it may be possible for some smaller players to jump into this market vacuum, but they'll face exactly the same problems: operating AI at scale is stupidly expensive. They can't be as 'cheap' as current AI services. As they can't afford to subsidise their AI service, they may still be too costly. I can see that smaller players can provide 'one-trick pony' AI services, like 'just for programming', as opposed to the generic AI services provided by the large players. But due to market demand they may become priced at: "if you have to ask, you can't afford it."

Self-hosting an AI with your own hardware is probably just as cost-prohibitive, even if you don't value your time. In part because a ton of people will get this idea at the same time, impacting hardware prices even more. And the operating costs of AI seem significant. Would it even be possible to setup your own AI and achieve the same productivity level?

Given current circumstances, I can see a scenario where the USA government will step in and subsidise these services. If the AI investors buy some specific crypto coins obviously.

Quid pro quo, Clarice.²

Hacker News thread

— You saw what I did there 😘 ↩
If justice would still be a thing, Antrax island would become quite crowded ↩

KVM migration from intel to AMD fails with missing cmp_legacy feature (+ solution)

2026-01-06T12:00:00+01:00

Context

I'm running a virtualisation lab environment, with four Intel-based CPUs (i5-6500) and one AMD Ryzen 3 PRO 2200GE.

When migrating virtual machines from one of the Intel hosts to the AMD host, the migration would fail with the following error:

error: operation failed: guest CPU doesn't match specification: extra features: cmp_legacy"

The really strange thing is that some virtual machines did migrate successfully from an Intel system to the AMD system without any issues.

So I dumped the XML of the virtual machines and compared them. It turns out that the virtual machines that migrated successfully were all single-core and all failing virtual machines were multi-core.

As the cmp_legacy CPU feature seems to be related to (lack of) support for hyper-threading, the configured CPU topology of the virtual machines was suspected to be the culprit.

I've configured a custom CPU topology on the virtual machines with 1 socket, 1 die and one or more CPU cores. This caused the migration failure.

Solution

If you configure multi-core virtual machines with multiple sockets instead of cores migration between Intel and AMD hosts will succeed.

In the past, migrations between an Intel and AMD host always succeeded, assuming that the appropriate CPU features were disabled. Why this suddenly stopped working is not clear to me, as this configuration never changed. Maybe it's related to a Libvirt update, but I have no proof for this.

Bose SoundLink on-ear headphones battery replacement

2025-02-25T12:00:00+01:00

Skip to the bottom two paragraph for instructions on how to replace the battery.

I bought my Bose SoundLink on-ear Bluetooth headphones for 250 Euros around 2017 and I really like them. They are small, light, comfortable and can easily fit in a coat pocket when folded.

Up until now (about 7 years later) I have replaced the ear cushions in 2019 (€25) and 2024 (€18).

Early 2025, battery capacity had deteriorated to a point where it became noticeable. The battery was clearly dying.

Unfortunately these headphones aren't designed for easy battery replacement:

Bose hasn't published instructions on how to replace the battery, doesn't offer a replacement battery and hasn't documented which battery type/model is used.
The left 'head phone' has two Torx security screws and most people won't have the appropriate screwdriver for this size
There is soldering involved

I wanted to try a battery replacement anyway as I hate to throw away a perfectly good, working product just because the battery has worn out. Maybe at some point the headband needs replacing, but with a fresh battery, these headphones can last another 7 years. Let's prevent a bit of e-waste with a little bit of cost and effort.

Most of all, the cost of this battery replacement is much lower than a new pair of headphones as the battery was €18 including taxes and shipping.

Right to repair should include easy battery replacement

Although my repair seemed to have worked out fine, it requires enough effort that most people won't even try. For this reason, I feel that it should be mandatory by law that:

Batteries in any product must be user-replaceable (no special equipment or soldering required)
Batteries must be provided by the vendor until 10 years after the last day the product was sold (unless it's a standard format like AA(A) or 18650).
Batteries must be provided at max 10% of the cost of the original product
The penalty for non-compliance should be high enough such that it won't be regarded as the cost of doing business

For that matter, all components that may wear down over time should be user-replaceable.

What you need to replace the battery

Buy the exact battery type: ahb571935pct-01 (350mAh) (notice the three wires!)
A Philips #0 screwdriver / bit
A Torx T6H security screwdriver / bit (iFixit kits have them)
A soldering iron
Solder
Heat shrink for 'very thin wire'
Multimeter (optional)
a bit of tape to 'cap off' bare battery leads

Please note that I found another battery ahb571935pct-03 with similar specifications (capacity and voltage) but I don't know if it will fit.

Putting the headphone ear cushion back on can actually be the hardest part of the process, you need to be firm and this process is documented by Bose.

Battery replacement steps I took

Make sure you don't short the wires on the old or new battery during replacement

The battery is located in the left 'head phone'.

Use a multimeter to check if your new battery isn't dead (should be 3+ volt)
Remove the ear cushion from the left 'head phone' very gently as not to tear the rim
Remove the two philips screws that keep the driver (speaker) in place
Remove the two Torx screws (you may have to press a bit harder)
Remove the speaker and be carefull not to snap the wire
Gently remove the battery from the 'head phone'
Cut the wires close to the old battery (one by one!) and cover the wires on the battery to prevent a short
Strip the three wires from the headphones a tiny bit (just a few mm)
Put a short piece of heat shrink on each of the three wires of the battery
Solder each wire to the correct wire in the ear cup
Adjust the location of the heat shrink over the freshly soldered joint.
Use the soldering iron close to the heat shrink to shrink it (don't touch anything), this can take some time, be patient
Check that the heat shrink is fixed in place and can't move
Put the battery into it's specific location in the back of the 'head phone'
Test the headphones briefly before reassembling the headphones
Reassemble the 'head phone' (consider leaving out the two Torx screws)
Dispose of the old battery in a responsible manner

My 71 TiB ZFS NAS after 10 years and zero drive failures

2024-09-14T12:00:00+02:00

My 4U 71 TiB ZFS NAS built with twenty-four 4 TB drives is over 10 years old and still going strong.

Although now on its second motherboard and power supply, the system has yet to experience a single drive failure (knock on wood).

Zero drive failures in ten years, how is that possible?

Let's talk about the drives first

The 4 TB HGST drives have roughly 6000 hours on them after ten years. You might think something's off and you'd be right. That's only about 250 days worth of runtime. And therein lies the secret of drive longevity (I think):

Turn the server off when you're not using it.

According to people on Hacker News I have my bearings wrong. The chance of having zero drive failures over 10 years for 24 drives is much higher than I thought it was. So this good result may not be related to turning my NAS off and keeping it off most off the time.

My NAS is turned off by default. I only turn it on (remotely) when I need to use it. I use a script to turn the IoT power bar on and once the BMC (Baseboard Management Controller) is done booting, I use IPMI to turn on the NAS itself. But I could have used Wake-on-Lan too as an alternative.

Once I'm done using the server, I run a small script that turns the server off, wait a few seconds and then turn the wall socket off.

It wasn't enough for me to just turn off the server, but leave the motherboard, and thus the BMC powered, because that's just a constant 7 watts (about two Raspberry Pis at idle) being wasted (24/7).

This process works for me because I run other services on low-power devices such as Raspberry Pi4s or servers that use much less power when idling than my 'big' NAS.

This proces reduces my energy bill considerably (primary motivation) and also seems great for hard drive longevity.

Although zero drive failures to date is awesome, N=24 is not very representative and I could just be very lucky. Yet, it was the same story with the predecessor of this NAS, a machine with 20 drives (1 TB Samsung Spinpoint F1s (remember those?)) and I also had zero drive failures during its operational lifespan (~5 years).

The motherboard (died once)

Although the drives are still ok, I had to replace the motherboard a few years ago. The failure mode of the motherboard was interesting: it was impossible to get into the BIOS and it would occasionally fail to boot. I tried the obvious like removing the CMOS battery and such but to no avail.

Fortunately, the [motherboard]¹ was still available on Ebay for a decent price so that ended up not being a big deal.

ZFS

ZFS worked fine for all these years. I've switched operating systems over the years and I never had an issue importing the pool back into the new OS install. If I would build a new storage server, I would definitely use ZFS again.

I run a zpool scrub on the drives a few times a year². The scrub has never found a single checksum error. I must have run so many scrubs, more than a petabyte of data must have been read from the drives (all drives combined) and ZFS didn't have to kick in.

I'm not surprised by this result at all. Drives tend to fail most often in two modes:

Total failure, drive isn't even detected
Bad sectors (read or write failures)

There is a third failure mode, but it's extremely rare: silent data corruption. Silent data corruption is 'silent' because a disk isn't aware it delivered corrupted data. Or the SATA connection didn't detect any checksum errors.

However, due to all the low-level checksumming, this risk is extremely small. It's a real risk, don't get me wrong, but it's a small risk. To me, it's a risk you mostly care about at scale, in datacenters³ but for residential usage, it's totally reasonable to accept the risk⁴.

But ZFS is not that difficult to learn and if you are well-versed in Linux or FreeBSD, it's absolutely worth checking out. Just remember!

Sound levels (It's Oh So Quiet)

This NAS is very quiet for a NAS (video with audio).

But to get there, I had to do some work.

The chassis contains three sturdy 12V fans that cool the 24 drive cages. These fans are extremely loud if they run at their default speed. But because they are so beefy, they are fairly quiet when they run at idle RPM⁵, yet they still provide enough airflow, most of the time. But running at idle speeds was not enough as the drives would heat up eventually, especially when they are being read from / written to.

Fortunately, the particular Supermicro motherboard I bought at the time allows all fan headers to be controlled through Linux. So I decided to create a script that sets the fan speed according to the temperature of the hottest drive in the chassis.

I actually visited a math-related subreddit and asked for an algorithm that would best fit my need to create a silent setup and also keep the drives cool. Somebody recommended to use a "PID controller", which I knew nothing about. So I wrote some Python, stole some example Python PID controller code, and tweaked the parameters to find a balance between sound and cooling performance.

The script has worked very well over the years and kept the drives at 40C or below. PID controllers are awesome and I feel it should be used in much more equipment that controls fans, temperature, and so on, instead of 'dumb' on/of behaviour or less 'dumb' lookup tables.

Networking

I started out with quad-port gigabit network controllers and I used network bonding to get around 450 MB/s network transfer speeds between various systems. This setup required a ton of UTP cables so eventually I got bored with that and I bought some cheap Infiniband cards and that worked fine, I could reach around 700 MB/s between systems. As I decided to move away from Ubuntu and back to Debian, I faced a problem: the Infiniband cards didn't work anymore and I could not figure out how to fix it. So I decided to buy some second-hand 10Gbit Ethernet cards and those work totally fine to this day.

The dead power supply

When you turn this system on, all drives spin up at once (no staggered spinup) and that draws around 600W for a few seconds. I remember that the power supply was rated for 750W and the 12 volt rail would have been able to deliver enough power, but it would sometimes cut out at boot nonetheless.

UPS (or lack thereof)

For many years, I used a beefy UPS with the system, to protect against power failure, just to be able to shutdown cleanly during an outage. This worked fine, but I noticed that the UPS used another 10+ watts on top of the usage of the server and I decided it had to go.

Losing the system due to power shenanigans is a risk I accept.

Backups (or a lack thereof)

My most important data is backed up trice. But a lot of data stored on this server isn't important enough for me to backup. I rely on replacement hardware and ZFS protecting against data loss due to drive failure.

And if that's not enough, I'm out of luck. I've accepted that risk for 10 years. Maybe one day my luck will run out, but until then, I enjoy what I have.

Future storage plans (or lack thereof)

To be frank, I don't have any. I built this server back in the day because I didn't want to shuffle data around due to storage space constraints and I still have ample space left.

I have a spare motherboard, CPU, Memory and a spare HBA card so I'm quite likely able to revive the system if something breaks.

As hard drive sizes have increased tremendously, I may eventually move away from the 24-drive bay chassis into a smaller form-factor. It's possible to create the same amount of redundant storage space with only 6-8 hard drives with RAIDZ2 (RAID 6) redundancy. Yet, storage is always expensive.

But another likely scenario is that in the coming years this system eventually dies and I decide not to replace it at all, and my storage hobby will come to an end.

This article was a Hacker News Hit

I needed the same board, because the server uses four PCIe slots: 3 x HBA and 1 x 10Gbit NIC. ↩
It takes ~20 hours to complete a scrub and it uses a ton of power while doing so. As I'm on a dynamic power tariff, I run it on 'cheap' days. ↩
enterprise hard drives used in servers and SANs had larger sector sizes to accommodate even more checksumming data to prevent against silent data corruption. ↩
every time I listen to ZFS enthusiasts you get the impression you are taking insane risks with your data if you don't run ZFS. I disagree, it all depends on context and circumstances. ↩
Because there is little airflow by default, I had to add a fan to cool the four PCIe cards (HBA and networking) or they would have gotten way too hot. ↩

The Raspberry Pi 5 is no match for a tini-mini-micro PC

2024-06-16T12:00:00+02:00

I've always been fond of the idea of the Raspberry Pi. An energy efficient, small, cheap but capable computer. An ideal home server. Until the Pi 4, the Pi was not that capable, and only with the relatively recent Pi 5 (fall 2023) do I feel the Pi is OK performance wise, although still hampered by SD card performance¹. And the Pi isn't that cheap either.

The Pi 5 can be fitted with an NVME SSD, but for me it's too little, too late. Because I feel there is a type of computer on the market, that is much more compelling than the Pi.

I'm talking about the tinyminimicro home lab 'revolution' started by servethehome.com about four years ago (2020).

A 1L mini PC (Elitedesk 705 G4) with a Raspberry Pi 5 on top

During the pandemic, the Raspberry Pi was in short supply and people started looking for alternatives. The people at servethehome realised that these small enterprise desktop PCs could be a good option. Dell (micro), Lenovo (tiny) and HP (mini) all make these small desktop PCs, which are also known as 1L (one liter) PCs.

These Mini PC are not cheap² when bought new, but older models are sold at a very steep discount as enterprises offload old models by the thousands on the second hand market (through intermediates).

Although these computers are often several years old, they are still much faster than a Raspberry Pi (including the Pi 5) and can hold more RAM.

I decided to buy two HP Elitedesk Mini PCs to try them out, one based on AMD and the other based on Intel.

The Hardware

	Elitedesk Mini G3 800	Elitedesk Mini G4 705
CPU	Intel i5-6500 (65W)	AMD Ryzen 3 PRO 2200GE (35W)
RAM	16 GB (max 32 GB)	16 GB (max 32 GB)
HDD	250 GB (SSD)	250 GB (NVME)
Network	1Gb (Intel)	1Gb (Realtek)
WiFi	Not installed	Not installed
Display	2 x DP, 1 x VGA	3 x DP
Remote management	Yes	No
Idle power	4 W	10 W
Price	€160	€115

The AMD-based system is cheaper, but you 'pay' in higher idle power usage. In absolute terms 10 watt is still decent, but the Intel model directly competes with the Pi 5 on idle power consumption.

Elitedesk 705 left, Elitedesk 800 right (click to enlarge)

Regarding display output, these devices have two fixed displayport outputs, but there is one port that is configurable. It can be displayport, VGA or HDMI. Depending on the supplier you may be able to configure this option, or you can buy them separately for €15-€25 online.

Click on image for official specs in PDF format

Both models seem to be equipped with socketed CPUs. Although options for this formfactor are limited, it's possible to upgrade.

Comparing cost with the Pi 5

The Raspberry Pi 5 with (max) 8 GB of RAM costs ~91 Euro, almost exactly the same price as the AMD-based mini PC³ in its base configuration (8GB RAM). Yet, with the Pi, you still need:

power supply (€13)
case (€11)
SD card or NVME SSD (€10-€45)
NVME hat (€15) (optional but would be more comparable)

It's true that I'm comparing a new computer to a second hand device, and you can decide if that matters in this case. With a complete Pi 5 at around €160 including taxes and shipping, the AMD-based 1L PC is clearly the cheaper and still more capable option.

Comparing performance with the Pi 5

The first two rows in this table show the Geekbench 6 score of the Intel and AMD mini PCs I've bought for evaluation. I've added the benchmark results of some other computers I've access to, just to provide some context.

CPU	Single-core	Multi-core
AMD Ryzen 3 PRO 2200GE (32W)	1148	3343
Intel i5-6500 (65W)	1307	3702
Mac Mini M2	2677	9984
Mac Mini i3-8100B	1250	3824
HP Microserver Gen8 Xeon E3-1200v2	744	2595
Raspberry Pi 5	806	1861
Intel i9-13900k	2938	21413
Intel E5-2680 v2	558	5859

Sure, these mini PCs won't come close to modern hardware like the Apple M2 or the intel i9. But if we look at the performance of the mini PCs we can observe that:

The Intel i5-6500T CPU is 13% faster in single-core than the AMD Ryzen 3 PRO
Both the Intel and AMD processors are 42% - 62% faster than the Pi 5 regarding single-core performance.

Storage (performance)

If there's one thing that really holds the Pi back, it's the SD card storage. If you buy a decent SD card (A1/A2) that doesn't have terrible random IOPs performance, you realise that you can get a SATA or NVME SSD for almost the same price that has more capacity and much better (random) IO performance.

With the Pi 5, NVME SSD storage isn't standard and requires an extra hat. I feel that the missing integrated NVME storage option for the Pi 5 is a missed opportunity that - in my view - hurts the Pi 5.

Now in contrast, the Intel-based mini PC came with a SATA SSD in a special mounting bracket. That bracket also contained a small fan(1) to keep the underlying NVME storage (not present) cooled.

There is a fan under the SATA SSD (click to enlarge)

The AMD-based mini PC was equipped with an NVME SSD and was not equipped with the SSD mounting bracket. The low price must come from somewhere...

However, both systems have support for SATA SSD storage, an 80mm NVME SSD and a small 2230 slot for a WiFi card. There seems no room on the 705 G4 to put in a small SSD, but there are adapters available that convert the WiFi slot to a slot usable for an extra NVME SSD, which might be an option for the 800 G3.

Noice levels (subjective)

Both systems are barely audible at idle, but you will notice them (if you sensitive to that sort of thing). The AMD system seems to become quite loud under full load. The Intel system also became loud under full load, but much more like a Mac Mini: the noise is less loud and more tolerable in my view.

Idle power consumption

Elitedesk 800 (Intel)

I can get the Intel-based Elitedesk 800 G3 to 3.5 watt at idle. Let that sink in for a moment. That's about the same power draw as the Raspberry Pi 5 at idle!

Just installing Debian 12 instead of Windows 10 makes the idle power consumption drop from 10-11 watt to around 7 watt.

Then on Debian, you:

run apt install powertop
run powertop --auto-tune (saves ~2 Watt)
Unplug the monitor (run headless) (saves ~1 Watt)

You have to put the powertop --auto-tune command in /etc/rc.local:

#!/usr/bin/env bash
powertop --auto-tune
exit 0

Then apply chmod +x /etc/rc.local

So, for about the same idle power draw you get so much more performance, and go beyond the max 8GB RAM of the Pi 5.

Elitedesk 705 (AMD)

I managed to get this system to 10-11 watt at idle, but it was a pain to get there.

I measured around 11 Watts idle power consumption running a preinstalled Windows 11 (with monitor connected). After installing Debian 12 the system used 18 Watts at idle and so began a journey of many hours trying to solve this problem.

The culprit is the integrated Radeon Vega GPU. To solve the problem you have to:

Configure the 'bios' to only use UEFI
Reinstall Debian 12 using UEFI
install the appropriate firmware with apt install firmware-amd-graphics

If you boot the computer using legacy 'bios' mode, the AMD Radeon firmware won't load no matter what you try. You can see this by issuing the commands:

rmmod amdgpu
modprobe amdgpu

You may notice errors on the physical console or in the logs that the GPU driver isn't loaded because it's missing firmware (a lie).

This whole process got me to around 12 Watt at idle. To get to ~10 Watts idle you need to do also run powertop --auto-tune and disconnect the monitor, as stated in the 'Intel' section earlier.

Given the whole picture, 10-11 Watt at idle is perfectly okay for a home server, and if you just want the cheapest option possible, this is still a fine system.

KVM Virtualisation

I'm running vanilla KVM (Debian 12) on these Mini PCs and it works totally fine. I've created multiple virtual machines without issue and performance seemed perfectly adequate.

Boot performance

From the moment I pressed the power button to SSH connecting, it took 17 seconds for the Elitedesk 800.

The Elitedesk 705 took 33 seconds until I got an SSH shell.

These boot times include the 5 second boot delay within the GRUB bootloader screen that is default for Debian 12.

Remote management support

Some of you may be familiar with IPMI (ILO, DRAC, and so on) which is standard on most servers. But there is also similar technology for (enterprise) desktops.

Intel AMT/ME is a technology used for remote out-of-band management of computers. It can be an interesting feature in a homelab environment but I have no need for it. If you want to try it, you can follow this guide.

For most people, it may be best to disable the AMT/ME feature as it has a history of security vulnerabilities. This may not be a huge issue within a trusted home network, but you have been warned.

The AMD-based Elitedesk 705 didn't came with equivalent remote management capabilities as far as I can tell.

Alternatives

The models discussed here are older models that are selected for a particular price point. Newer models from Lenovo, HP and Dell, equip more modern processors which are faster and have more cores. They are often also priced significantly higher.

If you are looking for low-power small formfactor PCs with more potent or customisable hardware, you may want to look at second-hand NUC formfactor PCs.

Stacking multiple mini PCs

The AMD-based Elitedesk 705 G4 is closed at the top and it's possible to stack other mini PCs on top.

The Intel-based Elitedesk 800 G3 has a perforated top enclosure, and putting another mini pc on top might suffocate the CPU fan.

As you can see, the bottom/foot of the mini PC doubles as a VESA mount and has four screw holes. By putting some screws in those holes, you may effectively create standoffs that gives the machine below enough space to breathe (maybe you can use actual standoffs).

Evaluation and conclusion

I think these second-hand 1L tinyminimicro PCs are better suited to play the role of home (lab) server than the Raspberry Pi (5).

The increased CPU performance, the built-in SSD/NVME support, the option to go beyond 8 GB of RAM (up to 32GB) and the price point on the second-hand market really makes a difference.

I love the Raspberry Pi and I still have a ton of Pi 4s. This solar-powered blog is hosted on a Pi 4 because of the low power consumption and the availability of GPIO pins for the solar status display.

That said, unless the Raspberry Pi becomes a lot cheaper (and more potent), I'm not so sure it's such a compelling home server.

This blog post featured on the front page of Hacker News.

even a decent quality SD card is no match (in terms of random IOPs and sequential throughput) for a regular SATA or NVME SSD. The fact that the Pi 5 has no on-board NVME support is a huge shortcomming in my view. ↩
in the sense that you can buy a ton of fully decked out Pi 5s for the price of one such system. ↩
The base price included the external power brick and 256GB NVME storage. ↩

IKEA $50 VINDSTYRKA vs. $290 Dylos air quality monitor

2023-09-17T12:00:00+02:00

This is a brief article in which I compare the IKEA VINDSTYRKA $50 air quality monitor (PM2.5) with a $290 air quality monitor made by Dylos to see if it's any good.

Context

If you care about indoor air quality, you may already own a CO2 to determine if it's time to ventilate your space a bit¹.

But a CO2 monitor doesn't tell you anything about the amount and size of particulate matter in the air.

Of particular interest are very fine particles, in the "PM2.5" category. Those particles are 2.5 micrometers or smaller in diameter can embed themselves deep inside the lungs and cause health issues.

Both air quality monitoring devices are specifically measuring PM2.5 particulate matter, so that's what we will focus on in this test.

DYLOS DC1100 PRO

I bought a Dylos DC1100 Pro in 2014 as I was quite interesting in the topic of air quality at that time. As I had to import the device, I believe I had to pay around 400 Euros for it but it's now for sale in the US for around $290.

click on the image for a picture of the back

I specifically chose this model because it has a serial port, which allows me to log data and maybe spot some trends. I was thinking about using this data to control my air circulation system in my home, but I never got around to building this.

This device (without serial port) is also explored in-depth by Matthias Wandel, who many of you probably know from his 1.7M subscribers Youtube channel. Tip: he shows the inside of the device.

Note that this video is from 10 years ago and I find it remarkable that the Dylos 1100 Pro is still sold - seemingly unmodified - over the years.

The IKEA VINDSTYRKA

Recently, I discovered that IKEA is now selling the VINDSTYRKA air quality monitor with support for Zigbee. The product is intended to be used with IKEAs range of air purifiers, to better finetune the behaviour of those devices.

The device measures PM2.5 particulate matter and also monitors temperature and humidity. All data is exposed over Zigbee. I've not tested this myself but I wonder how long it would last on a battery bank as it's USB powered.

Due to the low price tag, I decided to compare this $50 device (€40) with my Dylos. I think it's quite an interesting device because the Zigbee support allows you to integrate the device in home automation and log data, if you have a need for that.

Data logging setup

De Dylos device is a bit of a pain, because the measurement values are in particulates per square foot, so I had to find a proper conversion formula, which I found in this paper (page 17). The formula is:

PM2.5 Dylos DC1100 (μg/m3) = (particles > 0.5 μm minus particles > 2.5 μm)/250.

A Raspberry Pi 3B+ is running a Python script that reads the data from the serial port, converts it to PM2.5 values using the previous mentioned formula and transmits it into an InfluxDB + Grafana server.

To log the VINDSTYRKA data, I used a Sonoff Zigbee receiver on a Raspberry Pi 4b+. I installed zigbee2mqtt as a docker container, Mosquitto MQTT server and Telegraf+MQTT-client to submit the data into InfluxDB, which sounds more convoluted than it actually was.

Test method

I just let both devices run for a few days in close proximity to each other in my living room. I kept a balcony door open 24/7. I also created a bit of smoke at some point just to observe how the devices would respond and how much they would deviate from each other. Nothing too scientific, to be frank.

Test result

I've plotted the data from the Dylos and the Ikea device in the same graph and I think the results are quite straightforward. The peak in the middle was my 'smoke test'.

Original click on the image for a larger version

Updated click on the image for a larger version

After a few days I noticed a clear deviation between the VINDSTYRKA and the Dylos DC1100 Pro at certain time intervals. I have no real explanation for this deviation and I can't tell which device shows 'correct' data.

If I try to follow the AQI PM2.5 values for my city, the VINDSTYRKA seems to under report and the Dylos seems to over-report PM2.5 particulate matter.

Evaluation

Based on my test, I think the VINDSTYRKA is good enough, looking at how closely the measurements track the results of the Dylos.

Update September 19th 2023 Based on the new graph data, it seems the Dylos and VINDSTYRKA are less in agreement over absolute PM2.5 values. I'm not sure what to make of it.

As both devices still seem to agree on basic trend data, I would say that they still operate in the same ballpark.

Maybe you are a home automation enthusiast and you've managed to automate this process. ↩

Recycle your old laptop display and turn it into a monitor

2021-03-13T12:00:00+01:00

During a cleaning spree I decided that it was time to recycle two old laptops that were just collecting dust on a shelf for many years. Although I didn't have any purpose for them anymore, I realised that the displays were still perfectly fine.

This is the display of my old 13" Intel-based MacBook.

Somehow it felt wasteful to just throw the laptops out, I wondered if it would be possible to use these displays as a regular monitor?

It turns out: yes this is possible and it is also quite simple. My blogpost covers the same topic, with a few more pictures¹.

There is a particular LCD driver board that can be found all over ebay and the well-known Chinese webshops.

These boards cost around $20 and come with most things you need to get the display operational.

The board includes:

A small controller print for the on-screen display (center)
A high-voltage power supply for the backlight (left)
The data cable to drive the actual display (right)
Support for audio-passthrough + volume control (right corner)

The board doesn't include:

A 12-volt power supply
Some kind of frame to make the display and board one easy to handle unit

The board supports HDMI, VGA and DVI for signal input so it should work with almost any computer.

This particular board (M.NT68676.2) is used to power many different panel models. Although the board itself may be the same, it's important to order the board that is specifically tailored to the particular LCD panel you have. The panels seem easy to identify. This is the Macbook LCD panel type (LP133WX1 TL A1):

That TL/A1 part of the model is critical to finding the appropriate controller.

I also have an old Dell Vostro screen that uses the exact same driver board, but the cables are different. Also, it may be the case that the boards are flashed with the appropriate firmware for the particular panel. So I would recommend not to gamble and get the driver board that exactly matches the model number.

To make everything work, we first connect the high-voltage module to the backlight power cable...

...and we also connect the LCD driver cable:

When I connected everything for the first time, the display didn't work at all. It turns out that the board shipped with a second, separate interface cable and I had to swap those cables to make the display work properly.

Power supply

According to the sales page, the board requires a 12-volt 2A adapter, but in practice, I could get away with a tiny, much weaker power supply.

I found an old adapter from a Wi-Fi access-point (long gone) which is rated for just 0.5A. It did power both the board and the screen perfectly. It worked with both the Macbook display as the Dell display so it doesn't seem to be a fluke.

Although I didn't measure actual power consumption, we know that it can't be more than just 6 Watt because that's what the power adapter can handle.

Laptop displays need to be power efficient and that may also make them interesting for low-power or battery-powered projects.

We've only just begun

The display works, but that was the easy part.

The hardest part of this proces (not pictured) was switching the on-screen-display from Chinese (which I don't master) to English. But there is more work ahead.

At this point we end up with just a fragile LCD panel connected to a driver board through a bunch of wires. The whole setup is just an unpractical mess. There are at least two things left to do:

Mount the driver board, OSD controller and high-voltage unit to the back of the LCD panel
Make some kind of stand

For the old Dell display, I used a bit of wood and hot glue to make a wooden scaffold on which I could mount the driver board with a few screws. It won't win any prizes for sure but it's just an example of what needs to be done make the display (more) manageable.

It still doesn't have a stand but that's for another day. I can imagine that if you own a 3D printer, you can make a nice case with a stand, although that will increase the cost of the project.

Evaluation

What I like most about this kind of project is the fact that for very little money, you can recycle a perfectly fine and usable display that will probably last for another five to ten years. The project takes very little effort and it is also not difficult to do.

You can augment existing hobby projects with a screen and due to the relatively low power consumption, it may even be suitable for battery-powered projects.

And with a bit of work you can make a nice (secondary) monitor out of them. Finally you have an excuse to dust off one of your unused Raspberry Pis that you had to have but didn't have any actual use for.

The thrift-store is cheaper

If your goal is just to get a cheap LCD display, it may be cheaper to go to the nearest thrift-store and buy some old second-hand display for $10. But that may have some drawbacks:

It will be much larger than the laptop screen
It is powered by 110/220 volt so less suitable for a battery-powered setup
overall power consumption will be higher

So it all depends on your particular needs.

Closing words

If you also repurposed a laptop monitor for a project or just as a (secondary) screen, feel free to share your work in the comments.

I posted the article on slashdigit to hacker news and it got quite an interest. ↩

A 12.48 inch (1304x984) three-color e-paper display by Waveshare

2020-12-22T12:00:00+01:00

Introduction

Update September 2023: A small horizontal and large vertical row of pixels died. Demo of defective display here.

I'm running a solar-powered blog and I wanted to add a low-power display to show the daily solar 'harvest'¹ and maybe some additional information.

So I decided to use an e-paper display. I wanted a display that would be readable from a distance, so bigger would be better. I therefore chose the Waveshare 12.48 inch e-paper display².

an example based on data from the summer, generated with Graphite

This particular display costs $179 excluding taxes and shipping at the time this article was written.

Specifications

Waveshare sells a two-color (black and white) and a three-color version (black, white, red). I bought the three-color version. The three-color version is the (B) model.

Specifications:

Screen size     :      12.48 inches
Resolution      :      1304 x 984
Colors          :      black, white, red
Greyscale       :      2 levels
Refresh rate    :      16 seconds
Partial refresh :      Not supported
Interfaces      :      Raspberry Pi, ESP32, STM32, Arduino

The two-color variant of this display has a refresh rate of 8 seconds.

This display is clearly quite slow. Furthermore, the lack of partial refresh support could make this display unsuitable for some applications. I was OK with this slow refresh rate.

The image below demonstrates different fonts and sizes. I think DejaVuSansMono-Bold looks really well on the display, better than the font supplied by Waveshare.

The Interfaces

The display includes a microcontroller that in turn can be driven through one of four interfaces:

A Raspberry Pi (Worked)
An ESP32 (Not tested)
An Arduino (Didn't work)
An STM32 (Not tested)

I've tried the Arduino header with an Arduino Uno, but the supplied demo code didn't work. I did not investigate further why this was the case. It could be a problem with voltage regulation.

In the image above, the black plastic backplate is removed.

Image quality

These e-paper displays are mostly sold as product information displays for supermarkets and other businesses. However, the quality is good enough to display images. Especially the support for red can make an image stand out.

Below is an example of an image that incorporates the third (red) color.

The display seems suitable to display art.

It looks quite good in real life (sorry for the glare).

How the display shows three colors

The display acts like it is actually two displays in one. A black and white display, and a red and white display.

First, the black and white image is drawn. Next, the red and white image is put on top.

Because the display has to draw two images in succession, it takes 16 seconds to refresh the screen. This explains why the black-and-white version of this screen does a refresh in eight seconds: it doesn't have to refresh the red color.

Please note that the entire process of displaying content on the screen takes much longer.

A demonstration:

Displaying an image is cumbersome (On Raspberry Pi 3B+)

At the time this article was written, I could not find any information or tools for this display³.

Many Waveshare e-paper displays are popular and have a decent community support. However, it seems that this display is rather unknown.

Therefore, it seems that there are no tools available to display an arbitrary image on this display. You can use the example Python code to display an image but you have to follow these steps:

Create a black-and-white version of the image
Create a red-and-white version of the image, that contains only data for the red parts of the image
If the source image doesn't match the required resolution, you have to resize, crop and fill the image where appropriate.

Both 'black' and 'red' images need to exactly match the resolution of the display (1304x984) or the library will abort with an error.

As I found this proces tedious, I automated it.

A new tool to make displaying an image easy

I've used the python library as supplied by Waveshare and created a command-line tool (Github) on top of it to perform all the required steps as described in the previous section. I'm using Imagemagick for all the image processing.

The script works like this:

./display -i <image file> [--rotate 90] [--fuzz 35] [--color yellow]

The --fuzz and --color parameters may require some clarification.

The color red is extracted from an image but it's not always perfect. By applying the --fuzz parameter (the argument is a percentage), it is possible to capture more of the red (or selected color) of an image.

The --color option specifies which color should be 'converted' to red. By default this color is 'red' (obviously). The 'solar chart' (at the start of this article) is an example where a yellow line was converted to red.

Very slow: it takes about 55 seconds to display an image using the Raspberry Pi 3B+. Half of that minute is spend converting the images to the appropriate format using Imagemagick.

Informational: The Python program includes a modified version of the Waveshare Python library. This library has been altered to prevent double conversion of images, which significantly degrades image quality.

Slow performance

If you use the provided Python library (Python3 compatible) it takes about 30+ seconds to draw an image on the screen. (This excludes the image processing performed with the 'display' tool.)

Further testing showed that the Python library converts and dithers the image before it is sent to the display. And it does so for both black and red. Dithering is performed by looping in Python over every of the 1.3 milion pixels.

Each of these loops (for black and red) take about 10 seconds on the Raspberry Pi 3B+, which explains why it takes so long to update the display. Therefore, I think the combination of Python + the Raspberry Pi 3B+ is not ideal in this case.

Evaluation

I wanted to share my experience with this display to make other people aware of its existence. The tool I created should make it simple to get up and running and display an image.

It clearly has some drawbacks but due to the size, resolution and third color, it seems to be unique and may therefore be interesting.

Although I never tried the display with an ESP32, I think its an ideal for the purpose of a low-power picture frame.

This article was discussed on Hacker News (briefly). This resulted in about 9000 unique visitors for this article.

Appendix A - Remark on other displays

Please note: Waveshare also sells a smaller 10.3 inch black-and-white e-paper display for a similar price with some significant benefits:

Screen size     :      10.3 inches
Resolution      :      1872 x 1404
Colors          :      black and white
Greyscale       :      16 levels
Refresh rate    :      450 miliseconds
Partial refresh :      Supported

This particular display is smaller but has a higher resolution, supports 16 grayscale levels and updates in half a second. This display may better suit your particular needs. For example, I believe that this display may have been used in this project, a solar-powered digital photo frame.

Appendix B - How to make the display work on a Raspberry Pi

This information is straight from the Waveshare site but I include it for completeness and ease of use.

PART I: Enable the SPI interface with raspi-config

sudo raspi-config
select Interfacing Options
Select SPI
Select Yes
Reboot the Raspberry Pi

PART II: Install the required libraries

Install BCM283

Website

wget http://www.airspayce.com/mikem/bcm2835/bcm2835-1.60.tar.gz
tar zxvf bcm2835-1.60.tar.gz 
cd bcm2835-1.60/
sudo ./configure
sudo make
sudo make check
sudo make install

Install wiringPi

website

sudo apt-get install wiringpi
cd /tmp
wget https://project-downloads.drogon.net/wiringpi-latest.deb
sudo dpkg -i wiringpi-latest.deb
gpio -v

Caution: The library seems to be deprecated. The Raspberry Pi 4 is supported but future versions of the Raspberry Pi may not.

The wiringPi library is used as part of a compiled library called "DEV_Config.so" as found in the ./lib directory.

@raspberrypi:~/epaper_display $ ldd lib/DEV_Config.so 
    linux-vdso.so.1 (0x7ee0d000)
    /usr/lib/arm-linux-gnueabihf/libarmmem-${PLATFORM}.so => /usr/lib/arm-linux-gnueabihf/libarmmem-v7l.so (0x76f1e000)
    libwiringPi.so => /usr/lib/libwiringPi.so (0x76f00000)
    libm.so.6 => /lib/arm-linux-gnueabihf/libm.so.6 (0x76e7e000)
    libc.so.6 => /lib/arm-linux-gnueabihf/libc.so.6 (0x76d30000)
    libpthread.so.0 => /lib/arm-linux-gnueabihf/libpthread.so.0 (0x76d06000)
    librt.so.1 => /lib/arm-linux-gnueabihf/librt.so.1 (0x76cef000)
    libcrypt.so.1 => /lib/arm-linux-gnueabihf/libcrypt.so.1 (0x76caf000)
    /lib/ld-linux-armhf.so.3 (0x76f46000)

Install Python3 and required libraries

sudo apt-get update
sudo apt-get install python3-pip
sudo apt-get install python3-pil
sudo pip3 install RPi.GPIO
sudo pip3 install spidev

Apendix C - E-paper hacking

I see myself as a consumer and I don't have any desire to hack the display for lower refresh-rates or partial refresh support, with the risk of damaging the display in the process.

However one resource about this topic I find very informative is a video from the Youtube Channel "Applied Science" (By Ben Krasnow), called "E-paper hacking: fastest possible refresh rate".

Apendix D - Available libraries

Example code for all supported platforms can be found in this github location.

I also found this github repository that may support this display. This code (also) didn't work for me on my Arduino uno. This could be due to a voltage mismatch, but I'm not willing to solder and potentially destroy the display.

Apendix E - Links to other e-paper projects

Very large and expensive display (Medium paywall)

E-paper calendar

Solar-powered digital photo frame

During fall and winter, there is almost no power generation due to the very sub-optimal location of my balcony. ↩
You can go larger but at a cost. ↩
My google skills may be at fault but that point is now moot. ↩

Benchmarking a 1.44 MB floppy drive

2019-12-17T00:00:00+01:00

I've used fio - a storage benchmarking tool - to benchmark a 1.44 MB floppy drive to gauge its random I/O performance. I have no real reason for doing this. I just thought it was funny.

I've run a benchmark against the floppy drives for different queue depths. The results are shared below.

Random 4K Read performance

Random 4K Write performance

Conclusion

These images show that 1.44 MB a floppy drive have atrocious random I/O performance as compared to hard drives or solid state drives. Who knew!

Next: benchmarking random I/O performance of a tape drive. If somebody will lend me one.

Tools used

I used fio to benchmark the floppy drive. I've used fio-plot to generate the images. The benchmarks were run using an altered version of the benchmark script included with fio-plot.

Fio-plot: creating nice charts from FIO storage benchmark data

2019-11-28T00:00:00+01:00

New release of fio-plot

I've rewritten fio-plot, a tool that turns FIO benchmark data into nice charts. It allows you to create four types of graphs which will be discussed below.

The github project page explains how to run this tool.

Fio-plot also includes a benchmark script that automates testing with Fio.

The git repository also contains benchmark data, which can be used to test fio-plot.

2D bar chart

This chart plots IOPs and latency for various queue depths.

3D bar chart

2D line chart for log data

2D bar chart latency histogram

Additional images

The github repository also contains a folder with a lot of example images.

My home lab server with 20 cores / 40 threads and 128 GB memory

2019-08-13T00:00:00+02:00

Update fall 2024 I have decided to decomission this machine and it is no longer in use.

As of this moment, it's replaced by a cluster of four 1L PCs which use about a third of the idle power usage and boot within 20 seconds. The single-core performance of these low-power 1L PCs surpasses the performance of this older machine.

If I even decide to build a new lab server with a lot of cores and memory in a single machine, I'll build a regular system and won't use datacenter hardware anymore due to the noise and slow boot process.

I've bought a secondhand HP DL380p Gen8 server and I think it's awesome.

This machine has dual-processors, with each CPU having 10 physical cores and two threads per core, for a grand total of 20 cores / 40 threads for the entire machine. It's also equiped with 128 GB or memory.

Laughs in htop

I bought this machine because I wanted to have a dedicated server on which I run my home lab environment. This is the box on which I will try out new software, run experiments, test ideas and so on.

In this article I'd like to share some information about this machine and my experiences with it. Let's start with an overview of the specifications.

Update: this article featured on Hacker News, click here for the discussion thread.

HP DL380p Gen8 Specifications

Part	Description
Form factor	19" 2U rackmount
Processor	2 x Intel(R) Xeon(R) CPU E5-2680 v2 @ 2.80GHz
RAM	128 GB DDR3 (16 x 8GB)
Onboard LAN	4 x Broadcom 1 Gigabit (Copper)
RAID Controller	HP P420i
Storage	8 x 2.5" SAS/SATA slots (no media)
PSU	1 x 750 Watt
Power usage	about 110 Watt idle
KVM	HP iLO 4 with HTML5 console

Cost

I've bought this server for around 1500 Euro ($1700) including taxes (21%) and a one year warranty. I've bought it from the company https://creoserver.com (The Netherlands).

Update 2021: This kind / generation of hardware seems to be dumped on the market for less than half of what I paid for it at the time.

I believe that the price/performance balance for this server is quite good, but I let you be the judge of that.

The storage is based on some SSDs I already owned and some new SSDs I've bought separately. So the price is based on the chassis + storage caddies but without actual storage media.

Age

The HP DL380p Gen8 product generation was introduced in 2012. The configuration I have chosen is based on a CPU that was introduced in 2013. Based on the serial number I guess the chassis+motherboard is from 2014 (about 5 years old¹ at the time I bought it).

CPU - The Intel Xeon E5-2680 v2

The Intel Xeon E5-2680 v2 CPU originated from late 2013 and is based on the ivy bridge architecture. The base clock is 2.8 Ghz but it can turbo boost up to 3.6 Ghz. With 10C/20T per CPU and the dual-processor configuration it's needless to say that you can run quite a few virtual machines and/or containers in parallel on this machine, without even oversubscribing CPU cores.

You may ask what kind of performance you may expect from this box and how 2013 holds up in 2019. A high number of cores is nice, but the cores themselves fast enough?

The 2680v2 is a processor that sold for about $1700 (Intel Ark) when it came out in 2013. If you look at the list of Xeon processors from that timeframe, it was the top of the line Intel dual-processor compatible CPU with only the E5-2690 v2 processor above it, which ran only 200 Mhz faster (base clock).

There was almost nothing better at that time and people ran their companies on those machines so I think performance is more than enough. Especially for a lab environment (overkill is probably an understatement).

I've included some benchmark results below just for reference. You can use this information to make some comparisons to other CPUs that you are familiar with to get some sense of the performance.

I've also compared scores a little bit and I've noticed that people in the past were perfectly happy gaming on desktop systems with CPUs that have equal or less single core performance.

Geekbench 4 score

I've run Geekbench on the DL380p Gen8:

Single Core:  3525
Multi Core : 48764

Passmark

(source)

Single Core:  1788
Multi Core : 12612

Sysbench

root@dora:/home/ansible# sysbench --test=cpu --cpu-max-prime=20000 run
[.....]
General statistics:
    total time:                          10.0002s
    total number of events:              4358
[.....]

Some perspective: My intel Mac mini 2018 and my game pc from 2013 also hit 10 seconds runtime. For whoever thinks they should work with 'cheap' Raspberry Pi's, this is the sysbench score of a Raspberry Pi 3B+.

Test execution summary:
    total time:                          328.3016s

It's 32x slower. I really recommend to not use Pi's except for electronic projects. The performance is so bad, it's not worth it. Even a small VM on your desktop/laptop is already way faster.

Other benchmarks

I won't promise anything, but if it's not too much work I can run a benchmark if you have any suggestions. Feel free to comment down below or email me.

Memory

I've ordered this machine with 128GB of DDR3 memory. The memory consists of 16 x 8GB 1333Mhz memory modules. The machine has 12 memory slots per CPU so there are still 8 slots left to be filled if I ever feel a need to expand memory.

Storage

Drive slots

I've chosen a chassis with room for 8 x 2.5" drives. Depending on the chassis model, you can go up to 25 x 2.5" (Small Form Factor) or 12 x 3.5" (Large Form Factor).

Both SAS and SATA HDDs/SSDs are supported. You can't just stick HDDs or SSDs in the drive slots, you need to put your HDD/SSD first in an empty caddy, I bought those with the server.

The caddy has the LED lights build-in to signal the drive status. It has some electrical contacts at the back for those lights, it's not just a plastic 'sabot'.

My caddies tended to be a bit fragile, they came apart when trying to pull a drive out of the cage, but nothing broke and it all works fine.

Drive compatibility

HP servers can be picky about which HDD disk drives work or won't work. They all technically work, but sometimes the disk temperature cannot be read by the controller. In that case, the system fans will slowly start to spin faster and faster until almost maximum speed. This is obviously not workable.

Smaller HDD drives did work fine and the server stayed quiet. Only some 500GB HDD drives caused 'thermal runaway'.

I've found this table of supported and unsupported drives for HP controllers.

Overview of SSDs that are compatible

I've tested these SSDs:

- Samsung 860 Pro (consumer)
- Samsung PM833   (enterprise)
- Intel D3-S4610  (enterprise)
- Crucial MX200   (consumer)

P420i RAID mode vs. HBA mode

Important: you can't boot from the storage controller in HBA mode. You are left with booting from internal/external USB (2.0) or internal SD card.

I'm not sure if there is any significant performance difference between the two modes for SSDs. I just want to be able to boot from one of the drives, not from USB/SD card.

Storage management - ssacli tool

To configure the P420i RAID controller, It's highly recommended to install the ssacli tool from HP. Otherwise you have to reboot and wait 10 minutes (no joke) to enter the 'Smart Array Configuration Utility' to make changes to the storage configuration.

I just followed these instructions to install this tool on Ubuntu:

curl http://downloads.linux.hpe.com/SDR/hpPublicKey1024.pub | apt-key add -
curl http://downloads.linux.hpe.com/SDR/hpPublicKey2048.pub | apt-key add -
curl http://downloads.linux.hpe.com/SDR/hpPublicKey2048_key1.pub | apt-key add -
curl http://downloads.linux.hpe.com/SDR/hpePublicKey2048_key1.pub | apt-key add -

Contents of /etc/apt/sources.list.d/hp.list:

deb http://downloads.linux.hpe.com/SDR/repo/mcp/Ubuntu bionic/current non-free

For Debian:

deb http://downloads.linux.hpe.com/SDR/repo/mcp/debian bookworm/current non-free

Installing the software:

apt-get update
apt-get install ssacli

Some examples:

ssacli ctrl all show detail
ssacli ctrl slot=0 array all show detail
ssacli ctrl slot=0 ld all show detail
ssacli ctrl slot=0 pd all show detail
ssacli ctrl slot=0 ld 7 delete
ssacli ctrl slot=0 create type=ld raid=0 drives=2I:2:7 ss=8 ssdopo=off
ssacli ctrl slot=0 array i modify ssdsmartpath=disable
ssacli ctrl slot=0 pd 1 modify led=on

RAID vs non-RAID

You are forced by the RAID controller to always create a RAID array, even if you don't need the redundancy or performance.

I've chosen to just put SSDs in individual RAID0 logical drives, making them effectively individual drives from the perspective of the operating system. I'm not running a mission-critical application so this is fine for me.

A small downside is that the bright red square light on each drive will permanently glow up. That light signals truthfully that you cannot remove a drive without killing the 'array'. I've not seen any option to turn this off, which I can understand.

Sound / Noise level

Idle sound level

I've taken some sound measurements using my iPhone with an app, so how reliable this is, I don't know but it's something.

During boot time (full fan speed)  : 62 dB
Idle, booted into operating system : 50 dB

To set some expectations:

My very subjective opinion is that at 50 dB the sound level is reasonable for a server like this, but it's definitely not quiet. I would not be able to work, relax or sleep with this server in the same room.

Although this server is fairly quiet at idle, it does need its own dedicated room. When the door is closed, you won't hear it at idle, but under sustained load, you will hear high pitched fan noise even with a closed door.

Impact of adding a PCIe card on noise level

When you put any kind of PCIe card in the server, two of its six fans in-line with the PCIe expansion slot will run at 40%+ to cool these cards.

The sound level will become a bit annoying. I've not found any option to disable this behavior. This means that if you need to expand the server with additional network ports or other components, the server really needs a room with a closed door.

Please note that if you want to keep noise levels down but want to upgrade to 10Gbit networking, you could opt to configure the server with Flexlom 2 x 10Gbit instead of the stock Flexlom 4 x 1 Gbit copper. This will give you more bandwidth without the need to add a PCIe card.

At this time, I have no need to add any high-speed networking as I can run the simulations all on the machine itself (at least that's the plan).

Idle power usage

The DL380p has several BIOS settings that trade performance for (idle) power consumption. I have tested the performance and idle power usage for two power profiles:

HP Power Profile: Balanced Power and Performance
Present Power Reading: 76 Watts
Geekbench Single Core score: 2836

HP Power Profile: Static High Performance
Present Power Reading:  100 Watts
Geekbench Single Core score: 3525

Please note: that actual power usage includes +10 Watt for the iLO interface, to the system would use 86 Watt or 110 Watt at the wall outlet.

What we can learn from the above test results is that the high performance setting uses 31% more power at idle and in return you get 20% more single core performance.

The server supports (obviously) dual power supplies but that option only adds cost, increases power usage and gains me nothing. I'm not running a mission-critical business with this server.

By default, this server is turned off. When I want to do some work, I turn the server on using wake-on-lan. I do this with all my equipment except for my router/firewall.

Boot up time

I clocked 4 minutes and 28 seconds until I got a ping reply from the operating system.

KVM / iLO (Remote Management)

As with almost all HP servers, this machine has a dedicated remote management port + engine (iLO) so you can do everything remotely, such as powering the server on/off. You also have access to a virtual console (KVM over IP) and virtual CD-ROM drive to remotely provision the server.

For those of you who are less familiar with this hardware: notice the network interface left of the VGA connector. This is the iLO remote management interface. It's a mini computer with its own operatingsystem and IP-address, thus reachable from the network.

In the past iLO or similar solutions were a pain to use because you need Java or .NET to use the virtual console. With the ilO 2.7 update you will have a HTML5 interace, doing away with the need for both Java as .NET. This is a huge usability improvement.

Operating system

I'm currently running Ubuntu Linux 18.04 and using plain vanilla KVM to spawn virtual machines, wich works fine. Everything is maintained/configured with Ansible.

Closing words

I hope this overview was informative. Maybe it could be an option for yourself to consider if you ever want to setup a home lab yourself.

As far as I know this is not 100% reliable as the motherboard serial number can be changed to match the chassis when it's replaced due to failure. I guess it will have to do. ↩

HP Proliant Microserver Gen10 as router or NAS

2017-09-14T12:00:00+02:00

Introduction

In the summer of 2017, HP released the Proliant Microserver Gen10. This machine replaces the older Gen8 model.

For hobbyists, the Microserver always has been an interesting device for a custom home NAS build or as a router.

Let's find out if this is still the case.

Price

In The Netherlands, the price of the entry-level model is similar to the Gen8: around €220 including taxes.

CPU

The new AMD X3216 processor has slightly better single threaded performance as compared to the older G1610t in the Gen8. Overall, both devices seem to have similar CPU performance.

The biggest difference is the TDP: 35 Watt for the Celeron vs 15 Watt for the AMD CPU.

Memory

By default, it has 8 GB of unbuffered ECC memory, that's 4 GB more than the old model. Only one of the two memory slots is occupied, so you can double that amount just by adding another 8 GB stick. It seems that 32 GB is the maximum.

Storage

This machine has retained the four 3.5" drive slots. There are no drive brackets anymore. Before inserting a hard drive, you need to remove a bunch of screws from the front of the chassis and put four of them in the mounting holes of each drive. These screws then guide the drive through grooves into the drive slot. This caddy-less design works perfectly and the drive is mounted rock-solid in it's position.

To pop a drive out, you have to press the appropriate blue lever, which latches on to one of the front screws mounted on your drive and pulls it out of the slot.

There are two on-board sata controllers.

00:11.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] (rev 49)
01:00.0 SATA controller: Marvell Technology Group Ltd. 88SE9230 PCIe SATA 6Gb/s Controller (rev 11)

The Marvell controller is connected to the four drive bays. The AMD controller is probably connected to the fifth on-board SATA port.

As with the Gen8, you need a floppy-power-connector-to-sata-power-connector cable if you want to use a SATA drive with the fifth onboard SATA port.

Due to the internal SATA header or the USB2.0 header, you could decide to run the OS without redundancy and use all four drive bays for storage. As solid state drives tend to be very reliable, you may use a small SSD to keep the cost and power usage down and still retain reliability (although not the level of reliability RAID1 provides).

Networking

Just as the Gen8, the Gen10 has two Gigabit network cards. The brand and model is: Broadcom Limited NetXtreme BCM5720

As tested with iperf3 I get full 1 Gbit network performance. No problems here (tested on CentOS 7).

PCIe slots

This model has two half-height PCIe slots (1x and 8x in a 4x and 8x physical slot) which is an improvement over the single PCIe slot in the Gen8.

USB

The USB configuration is similar to the Gen8, with both USB2 and USB3 ports and one internal USB2 header on the motherboard.

Sidenote: the onboard micro SD card slot as found in the Gen8 is not present in the Gen10.

Graphics

The Gen10 has also a GPU build-in but I have not looked into it as I have no use for it.

The Gen10 differs in output options as compared to the Gen8: it supports one VGA and two displayport connections. Those displayport connectors could make the Gen10 an interesting DIY HTPC build, but I have not looked into it.

iLO

The Gen10 has no support for iLO. So no remote management, unless you have an external KVM-over-IP solution.

This is a downside, but for home users, this is probably not a big deal. My old Microserver N40L didn't have iLO and it never bothered me.

And most of all: iLO is a small on-board mini-comuter that increases idle power consumption. So the lack of iLO support should mean better idle power consumption.

Boot

Both Legacy and UEFI boot is supported. I have not tried UEFI booting.

Booting from the 5th internal SATA header is supported and works fine (as opposed to the Gen8).

For those who care: booting is a lot quicker as opposed to the Gen8, which took ages to get through the BIOS.

Power Usage

I have updated this segment as I have used some incorrect information in the original article.

The Gen10 seems to consume 14 Watt at idle, booted into Centos 7 without any disk drives attached (removed all drives after booting). This 14 Watt figure is reported by my external power meter.

Adding a single old 7200 1 TB drive drives power usage up to 21 Watt (as expected).

With four older 7200 RPM drives the entire system uses about 43 Watt according to the external power meter.

As an experiment, I've put two old 60 GB 2.5" laptop drives in the first two slots, configured as RAID1. Then I added two 1 TB 7200 RPM drives to fill up the remaining slots. This resulted in a power usage of 32 Watt.

Dimensions and exterior

Exactly the same as the Gen8, they stack perfectly.

The Gen8 had a front door protecting the drive bays connected to the chassis with two hinges. HP has been cheap on the Gen10, so when you open the door, it basically falls off, there's no hinge. It's not a big issue, the overall build quality of the Gen10 is excellent.

I have no objective measurements of noise levels, but the device seems almost silent to me.

Evaluation and conclusion

At first, I was a bit disappointed about the lack of iLO, but it turned out for the best. What makes the Gen10 so interesting is the idle power consumption. The lack of iLO support probably contributes to the improved idle power consumption.

The Gen8 measures between 30 and 35 Watt idle power consumption, so the Gen10 does fare much better (~18 Watt).

Firewall/Router

At this level of power consumption, the Gen10 could be a formidable router/firewall solution. The only real downside is it's size as compared to purpose-built firewalls/routers. The two network interfaces may provide sufficient network connectivity but if you need more ports and using VLANs is not enough, it's easy to add some extra ports.

If an ancient N40L with a piss-poor Atom processor can handle a 500 Mbit internet connection, this device will have no problems with it, I'd presume. Once I've taken this device into production as a replacement for my existing router/firewall, I will share my experience.

Storage / NAS

The Gen8 and Gen10 both have four SATA drive bays and a fifth internal SATA header. From this perspective, nothing has changed. The reduced idle power consumption could make the Gen10 an even more attractive option for a DIY home grown NAS.

All things considered I think the Gen10 is a great device and I have not really encountered any downsides. If you have no problems putting a bit of effort into a DIY solution, the Gen10 is a great platform for a NAS or Router/Firewall, that can compete with most purpose-build devices.

I may update this article as I gain more experience with this device.

Affordable server with server-grade hardware part II

2014-06-20T12:00:00+02:00

If you want to build a home server, it may be advised to actually use server-grade components. I documented the reasons for choosing server-grade hardware already in an earlier post on this topic.

It is recommended to read the old post first. In this new post, I only show new hardware that could also be chosen as a more modern hardware option.

My original post dates back to December 2013 and centers around the popular X9SCM-F which is based on the LGA 1155 socket. Please note that the X9SCM-F / LGA 1155 based solution may be cheaper if you want the Xeon processor.

So I'd like to introduce two Supermicro motherboards that may be of interest.

Supermicro X10SLL-F

Some key features are:

2 x Gigabit NIC on-board
6 onboard SATA ports
3 x PCIe (2 x 8x + 1 x 4x)
Costs $169 or €160

This board is one of the cheapest Supermicro boards you can get and it has 3 x PCI-e, which may be of interest if you need to install extra HBA's or RAID cards, SAS expanders and/or network controllers.

Supermicro X10SL7-F

This board is about $80 or €90 more expensive than the X10SLL-F but in return, you get eight extra SAS/SATA ports, for a total of 14 SATA ports. With 4 TB drives, this would give you 56 TB of raw storage capacity. This motherboard provides a cheaper solution than an add-on HBA card, which would occupy a PCIe slot. Hoever, the's a caveat: this board has 'only' two PCIe slots. But there's still room for an additional quad-port or 10 Gbe NIC and an extra HBA if required.

2 x Gigabit NIC on-board
6 onboard SATA ports
8 onboard SAS/SATA ports via LSI 2308 chip
2 x PCIe (8x and 4x)
Costs $242 or €250

Overview of CPU's

CPU	Passmark score	Price in Euro	Price in Dollars
Intel Pentium G3420 @ 3.20GHz	3459	55 Euro	74 Dollar
Intel Core i3-4130 @ 3.40GHz	4827	94 Euro	124 Dollar
Intel Xeon E3-1230 V3 @ 3.30GHz	9459	216Euro	279 Dollar

Dollars are from Newegg, Euro's are from Tweakers.net.
Euros are including taxes.

HP Proliant Microserver N40L is a great NAS or Router

2012-07-29T09:00:00+02:00

Update 2012-12-11: It seems that a new and faster version is on the horizon.

Update 2012-12-21: Yes, the new model G7 N54L is out.

Some products seem almost too good to be true and I think the HP Proliant Microserver N40L is one of them. If you are into the market for a very small, silent, efficient, yet capable home server, please take this device into consideration. I picked this device up for 200 euro's which is a bargain in my opinion.

First, take a look. As you can determine from the size of the 5 1/4 inch bay, this device is really small. The fun thing is though, that behind that door is room for four 3.5 inch SATA hard drives.

So you can put four large SATA disks into this device. It is just ideal as a home NAS, without resorting to expensive QNAP or Synology devices, which may not give you the flexibility you want.

The on-board RAID controller only seems to support RAID 0 and RAID 1. If you want to make a NAS out of this device you want to go for RAID 5. So you have two options.

Buy an additional hardware RAID controller that supports RAID 5;
Use Linux or BSD software RAID and don't spend a dime.

Processor

It contains the AMD equivalent of Intel's Atom processor, the Turion II Neo N40L dual-core, which runs at 1.5 Ghz. This CPU is not fast, but it is energy efficient and it helps keeping the device silent and cheap.

Memory

The device contains just 2 GB of ECC RAM. Sufficient for most tasks, but you can crank it up to 8 GB. The fact that you get ECC RAM in this device is a real plus, making this device extra reliable.

Disks

By default, a 250 GB disks is included. How they do that for this money is something I don't get. This disk takes up one of the four drive bays.

Personally, I would not use the 5 1/4 slot for an optical drive, (who uses them anyway in a server), instead, I would look into a solution where you can put the stock drive into that space, to make room for an additional disk for file storage. Useful in case you are building a NAS.

You may even install additional 2.5" disks with solutions like this.

Expansion

The microserver has two half-height PCIe slots, one x16 and one x1. It has also an esata connector at the back, so you can connect an external disks for backups or something. There are two USB ports at the back, four at the front. I wish they put four at the back and two at the front.

Environment

The device is very economic, I estimate power consumption at about 25 watt when idle. I measured 35 watt through my UPS, but there where also two external disk drives and a network switch connected to the UPS.

Noise levels are also excelent. There are just two fans. One very large fan at the back, that just seem to cool the entire device. The second fan is housed inside the tiny power supply, but although it is small, the fan makes little noise. When it is idle, you don't hear this server running.

Compatibility

I was able to install Ubuntu 12.04 LTS out-of-the-box. Is running fine. I didn't test any other operating systems.

Reason for purchase

I wanted to replace my Linux router (an old Mac Mini) with a device that can house two disk drives, so I could implement RAID 1. I use it as a Router/Firewall. But I also run a website on it, some monitoring software, so that's why I didn't want to buy a regular Linksys or Zytel embedded router.

Although this server has only one network interface, I use VLAN tagging with a VLAN-capable switch, so this is not a problem. Otherwise, I would just add a second Gigabyte half-height PCIe NIC.

Final words

It's an ideal device for any computer enthousiast who wants more flexibility than a standard NAS or embedded router can offer. It's cheap, small, silent and power efficient. Those HP engineers who created this device should get a thumbs up.

Buying a new computer

2011-04-03T15:43:00+02:00

*** Desktop or Laptop ***

When deciding on which computer to buy, the first decision you have to make is about whether to go for a desktop or a laptop. There was a time that many believed that the desktop would become a niche product. Most people want a laptop because they can take their computer everywhere they want to. Or at least lie on the couch while surfing.

If you want a laptop that also must replace your desktop, it must have a good screen, be fast and have lots of storage. And laptops are so good these days, they can be desktop replacements. Even if you buy a small laptop, they can still be fast and when necessary, you just hook up an external display, mouse and keyboard.

This is how I worked for many years and I still do. But I consider switching back to a desktop-based computer.

*** Mac and PC ***

I have two computers. The first one is an Intel-based Macbook (black) mid-2007, which is my main computer. The second one is a custom-build PC running Windows, solely for the purpose of gaming. This PC is based on Intel's Core i7 920, with 6 GB of RAM, so it's quite fast, even for today standards.

Both Macbook and PC are connected to a DVI KVM switch, that allows me to switch the keyboard, video and mouse between those systems. They thus both share my EIZO 24" (1920x1200) screen, keyboard and mouse.

Apart from these systems, I own an iPhone and an iPad.

*** Replacing my Macbook ***

For the last half year, I started to get annoyed with my Macbook. It just got slow. I put in a faster hard drive, but to no avail. The Macbook wasn't responsive enough. So I started thinking about replacing my Macbook. The first thing I realised that I do not need a laptop. I have an iPhone and an iPad, so sending emails, reading web pages, no problem. I do not tend to work on my Macbook outside of my house. So I don't think I need the mobility of a laptop. I want a fast but quiet, affordable computer attached to a high-resolution screen.

If you are a Mac user, there are three options: an Mac mini, an iMac or a Mac pro. I consider the Mac mini to low on specs and the Mac pro is just way too expensive. That leaves the option of an iMac.

*** Going for an iMac ***

Since I love high-resolution displays, the iMac 27" does appeal to me very much. The screen is just gorgeous. And you can put an Intel Core i7 into it, so it can be fast too. Even the video card is decent enough to play most games, either on Mac OS X or on Windows using Bootcamp.

Then after a discussion with a friend, I realised that the iMac would replace my PC. And my EIZO screen. New iMacs will probably arrive this summer, sporting even better processors, video cards, probably Thunderbolt. So I think I've made up my mind. I would still have my 'old' Macbook if I really needed any mobility. But I expect that once I have an iMac, both my PC and my Macbook are better off in the hands of somebody else. And I will need the money, an iMac is not cheap.

Thinking about this all led me to believe that in general, I would rather go for a setup with an iMac and a very thin plus lightweight laptop like the Macbook Air, than to buy a chunky desktop-replacing laptop like a Macbook pro. The big advantage of the latter is that you always have all your stuff with you. But you pay a price. The first thing is the weight. I really dislike the weight of my Macbook at 2+ kilos. The second thing is the fact that you always have to (dis)connect all these cables every time you switch between "desktop mode" and "laptop mode". The third thing is the noise. When putting some strain on the processor and/or video card, laptops tend to get noisy.

A desktop can give you true performance while still keeping things quiet and provide you with ample screen real estate. A netbook-like device such as the Macbook Air can give you true portability. I won't buy a Macbook Air, but this would be a really nice setup. The only thing you need to fix is the syncing problem. But there are services like Dropbox that may help you with that.

*** Keeping my Macbook alive ***

My PC has an Intel X25-M Postville 160 GB SSD installed as a fast boot disk. Since I couldn't stand the unresponsiveness of my Macbook anymore, I decided to put this SSD into my Macbook. This is cheaper than buying a new mac and I want to wait for that until the new iMac models arrive.

Installing the SSD made my Macbook come alive again. The Macbook only sports a SATA 150 interface, but it's not about throughput. It's about random IO performance. I am very happy with the result, there is less of an urgent 'need' to replace the Macbook in the near future. I can wait calmly on the new iMacs and decide then what I want.

*** Other people's thoughts ***

There is also this podcast where John Gruber of Daring Fireball is telling about is his purchase of a Macbook Air and suggesting that he will replace his Macbook Pro 15" with an iMac eventually.

Some pretty NAS case designs

2011-01-08T19:00:00+01:00

If you are planning on building your own NAS box, I have some suggestions regarding the case.

In my opinion, most computer case designers have absolutely no taste. Antec and Lian Li do create nice cases, but not that spectacular. And Lian Li is just very expensive. A fairly new company called Fractal Design seems to be different. To me, their designs are a breath of fresh air. For instance, if you want to build just a small NAS system and you think that 6 drives is enough, take a look at this beauty:

Just a small box with room for 6 drives. No hot swap stuff, but for personal use, that is not that important I guess. Unfortunately, I also found this review which also agrees that the case is pretty but there are some drawbacks. Too bad. I would still want to see more of such cases, but maybe with a better designed interior.

If you want to store more drives, Fractal Design seems to have another nice case in store:

More like a regular computer case but small and very sleek. Has room for 6 drives but you can use the 5,25 inch slots to store two or three additional drives. It is still very small. It's fairly new, I found no product reviews.

If that is not enough, just take a look at the Define R3 case:

Seems very pretty to me, has room for 8 disks by default and can host at least 10 disks if you also use the 5,25 inch slots. This review is quite positive about the case.

A rather old case from Chieftec which I still like and is quite cheap:

This case is not in the same league as the Fractal cases, but is cheaper and still does the trick. I used this case to build my first NAS and I don't have much to complain. It is no problem to fit in 10 disks. There are two things to note:

there are no filters on the case. You have to create something yourself.
De space between the side panel and the drive connectors is 'limited'.

If you have any suggestions for nice NAS cases, feel free to leave a comment.

Belkin Gigabit USB 2.0 adapter works perfectly with Linux

2010-12-08T20:53:00+01:00

My ISP upgraded my internet connection speed to a whopping 120 Mbit. I am using a mac mini as my internet router. As you may be aware, the mini has only one network interface, so I added a second interface using a USB to ethernet adapter. This adapter was limited to 100 Mbit, so to make full use of the 120 Mbit connection, I had to upgrade this adapter.

I took the gamble and bought the Belkin Gigabit USB 2.0 adapter. I could not figure out if it would work with Linux, but on the box it officially supports Mac OS X, which is always a good sign.

This adapter is recognized by Debian Linux without a hitch:

Mini:~# ethtool -i eth0
driver: asix
version: 14-Jun-2006
firmware-version: ASIX AX88178 USB 2.0 Ethernet
bus-info: usb-0000:00:1d.7-5

lsusb output:

Bus 005 Device 004: ID 050d:5055 Belkin Components F5D5055 Gigabit Network
Adapter [AX88xxx]

I did not test the actuall performance of this adapter, but it at least goes beyond the 100 Mbit (it does 120 Mbit at least). I expect it to be limited at say max 300 Mbit, being constrained by the maximum speed of USB 2.0.

Debian Lenny and Dell R410 network card not supported

2010-08-20T19:53:00+02:00

For those who are running Debian Lenny and want to order the new Dell R410 server, beware!

There is no safe solution to get Debian Lenny working with the on-board Broadcom network cards. A fairly recent kernel is required. Basically, you will have to install back-ported kernels, more recent modules and thus must violate the reasons why you were running Debian Lenny in the first place.

There is one solution, although it may not be an option: run VMware on the hardware and run Debian Lenny in a virtual machine. I think that in most cases, this will be sufficient for many cases and it has all the benefits of virtualisation and the stability of Debian Lenny.

It is unfortunate that Broadcom or Dell do not support Debian.

If you do have an easy and quite safe solution to get the Broadcom network cards working with Debian Lenny, please drop a note.

Beware though: the H200 and H700 RAID controllers are also not supported by Debian Lenny.

dell-s300-h200-and.html

Blu Ray is dead

2009-10-05T19:12:00+02:00

HD-DVD may be dead, but Blu Ray is just as dead. The whole concept of optical media is dead. Honestly, who is still burning CD's or DVD's nowadays? (If you are, why for Christ sake? I can't think of a single good reason) And at 10 euros ($100) for a single Blu Ray disk, you must be totally bonkers to buy one of them recorders.

I mean, let's face it, CD's were really cool in an age where 650 MB was way more than the 40 or 80 MB hard drive in your computer. It made a difference. That was already less so with a DVD, with a capacity of 'only' 4 GB. However, in the early years of the DVD, you could backup your entire hard drive on two, maybe three disks, since a hard drive averaged around 4 to 10 GB at that time.

Then finally came Blu Ray and HD-DVD. A whopping 25 GB on a disk. No shit!. You mean, like I need no less than 40 Blu Ray disks (400 euros) and an eon of burning disks to backup one of my 1 TB hard drives that cost me like 70 euros?

What must they have been thinking when they developed Blu Ray? As a backup medium it is useless, but it was ofcourse intended as a carrier for movies, I know. But why should I go outside, through the cold and the rain to go to some shitty video store that only has last years block busters? Why bother with 40 Mbit downstream and the Internet at your disposal? Downloading a movie will take me as much time as going to the video store and selecting something so dreadful even the DVD player will refuse to play it. What else is there to choose from. The Internet provides us with the most rare and obscure but most beautifull movies you ever saw. And the more main stream movies can be obtained in full HD 1080p.

Current Internet connections are of such quality, that physical media such as Blu Ray disk are becomming irrelevant. A normal DVD is downloaded within 20 minutes at 4 MB/s. And when Internet connections will reach 100 Mbit or 12 MB/s, even a HD 1080p movie will be downloaded within the hour.

Storage is not a problem. If you can store 40 HD movies on a single 1 TB disk, then you will pay 1,5 euros for each movie. Beats any Blu Ray disk in price and time. If you even care about them that much, buy or build a NAS and store them on some redundant storage.

In time people will do with DVDs and CDs what most people already do with CDs: rip them to some format your computer understands (to transfer it to your MP3 player) and get rid of that CD that will become scratched and useless even if you don't touch it. No, you don't want to transcode your HD movies to some iPod or something, but you may want to stream it to your media player in the living room? A jukebox full of films, just as you have a jukebox full of music.

Give the CD, DVD and Blu Ray a little push, and let them fall into the grave. It is an outdated technology for a problem that existed 10 years ago. The Internet has made it irrelevant. Be done with it.

Got myself a Norco RPC-4020

2009-06-16T19:47:00+02:00

I've got this fetish for storage. So I bought a case that gives me some room for future expantion. The current 6 TB RAID 6 storage server does not have any room for expantion.

This Norco RPC-4020 case with 20 hot swap drive bays does however. Don't know what to fill it with yet.

FFmpeg performance on a Core i7 920 @ 3.6 Ghz

2009-04-22T23:10:00+02:00

The system i'm running is a Core i7 920 @ 3.6 Ghz.

I am transcoding a DVD (Grave Of The Fire Flies) to iPod format (640x480 x264).

Thread support is enabled, to FFmpeg uses about 250% CPU. That's 2.5 of the 4 cores available. If possible, I would have liked to see it use all four to the max.

Any way. I use these settings:

FFmpeg version SVN-r18628

ffmpeg -i $1 -pass 1 -acodec libfaac -ab 128k -ac 2 -vcodec libx264 -vpre normal -vpre ipod640 -s 640x480 -b 512k -bt 512k -threads 0 -f mp4 $2

With these settings, I get an encoding speed of fps=193.

I don't know how that stacks up against other systems. It seems fast to me though. In effect, the system is playing the DVD at 7.6 times the speed of the movie (25 fps?). So encoding is 88 minutes / 7.6 = 11.45 minutes for encoding a DVD to iPod x264.

Core i7 920 @ 3,6 Ghz is a true beast!

2009-03-04T21:19:00+01:00

Even today, Core 2 Duo processors clocked at 2 ghz are no slugs. However, the Core i7 920 is of a different kind. First, it is not only clocked at a higher speed (default 2,8 Ghz), it is also a quad-core processor. Thanks to the re- introduction of hyperthreading, this processor can handle 8 parallel proceses simultaneously.

Just how fast a Core i7 can be, especially if overclocked to 3,6 Ghz shows this diagram:

Using my still in development version of PPSS, four systems processed 400 GB of WAV files and converted them to MP3. This simple pie-chart shows that the Core i7 on it's own, using 8 parallel processes, managed to process 2/3 of the files. The Core i7 was way faster than the other 3 systems combined! This is marvelous, I think. And it seems all due to Hyperthreading. If an additional duo core system would have been added, the other systems combined would have also 8 parallel threads available and would have processed roughly 50% of the items. However, please note that the Core i7 is a quad core processor and has 'only' four physical cores...

Benefits of hyper-threading on a Core 7i processor

2008-12-28T00:26:00+01:00

I had some wave files that I wanted to encode to mp3. I wrote a small parallel processing framework for this job. It executes parallel jobs so I can benefit from the 4 cores + 4 virtual cores of my new Core 7i 920 processor.

The framework is based on some shell scripts running on Linux (or probably any other unix) and Lame.

I wanted to test how much impact hyperthreading has on parallel performance. Hyperthreading has a bit of a bad reputation, dating back from the P4 erra. Lots of 'hype' but no significant performance gain.

I ran some test with hyperthreading enabled and disabled (within the bios).

In this test I used 16 wav files and encoded them to mp3 with Lame under Linux. The data in the table are raw measurements.

As you can see, the benefit of HT is there and can improve processing speed with up to 24 percent.

As more threads are run simultaneously, processing speed is significantly improved comparted to non-HT.

Highpoint RocketRAID 2320 on Debian howto

2008-09-28T08:06:00+02:00

Get the 'open source' driver from www.highpoint-tech.com. (It's not open source, it uses a closed binary driver.)

http://www.highpoint-tech.com/USA/bios_rr2320.htm

Install the kernel headers if you haven't already

- apt-get install linux-headers-2.6.18-6-k7

- extract the downloaded driver with tar xzf

- cd product/rr232x/linux

- type 'make'

As of 28 september 2008, this gives no errors.

However, a 'make install' will fail. This is cause by the fact that the installation script uses mkinitrd, which is obsolete: the mkinitramfs command should be used. So we have to edit a script.

**Update Dec 2009: the latest drivers do not need the following steps anymore.

- vi osm/linux/install.sh

- replace all occurrences of mkinitrd with mkinitramfs ( press : and type
%s/mkinitrd/mkinitramfs/g and then :wq)

Continue here:

- Go back to the product/rr232x/linux directory and type 'make install'.

That's it.