Louwrentius

Just the answer:

By default, on Debian, the scroll back buffer is about 1K lines. This can be changed in the .screenrc file in your home directory. The following example sets the scroll back buffer to 5K lines.

defscrollback 5000

Set the scroll back buffer on the fly with:

First enter the command line mode:

ctrl + a, :

Then enter:

scrollback 2000

To set the scroll back buffer to 2000 lines.

To actually scroll back, the actuall stuff why you may be reading this post:

First enter copy mode:

ctrl + a, [

Use standard VI controls to navigate through the lines (h j k l).

Use ctrl+b to scroll a full page up

Use ctrl+f to scroll a full page down.

For more details, please visit this link:

scrollback-buffer/

The speed at which files are compressed with gzip is currently almost always determined by the speed of the CPU. However, standard unix gzip is single- threaded and only uses a single CPU (core).

However, the maintainer of the zlib library has released 'pigz' or 'pig-zee' whichs adds just that: support for parallel compression. This dramatically improves the speed at which a file can be gzipped.

In this example, a 3 GB compressable file is gzipped:

Gzip:

root@Core7i:~# time gzip pigz.bin

real 1m58.994s

user 1m56.480s

sys 0m1.820s

Pigz:

root@Core7i:~# time pigz pigz.bin

real 0m31.524s

user 2m54.890s

sys 0m2.900s

This simple and a bit unscientific example shows a 400% speed improvement. Since the Core i7 has four real cores, this shows that pigz scales nicely.