Compcache

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This command is run in the standard Linux environment via the Terminal Activity. The GUI will probably not integrate comfortably with the XO Laptop's Sugar environment. Your user experience may vary considerably depending on the established environment and the other programs running on the laptop, may need re-installation after an OS Update. See the Linux software category for other commands.

Contents


LINUX COMMAND

compcache

This project creates RAM based block device (named ramzswap) which acts as swap disk. Pages swapped to this disk are compressed and stored in memory itself.

Compressing pages and keeping them in RAM virtually increases its capacity. This allows more applications to fit in given amount of memory. This is especially useful for:

  • Embedded Devices: Memory is scarce and adding more memory increases device cost. Also, flash storage suffers from wear-leveling issues, so its useful if we can avoid using them as swap device.
  • Small Desktops (aka Virtual Machines!): De/Compression is much faster than swapping to disks (include seek times!). Of course, you also get to run VMs with much less RAM assigned. Total memory savings from individual VMs can be quite significant if multiple VMs are hosted.
  • LiveCDs : These typically do not have any disk swap configured.

Functions

Install Notes

From Linux (or XO terminal), pre-setup tools can be installed via root

$ yum -y install make autotools gcc
-----------// needs updating // 
=============================================================================
Installing:
 mc                      i386       1:4.6.1a-45.20070124cvs.fc7  olpc_development 2.1M
Installing for dependencies:
 perl                    i386       4:5.8.8-27.fc7   olpc_development   10 M                 [*]
 perl-libs               i386       4:5.8.8-27.fc7   olpc_development  567 k                 [*]
 slang                   i386       2.0.7-2.fc7      olpc_development  329 k
 
Transaction Summary
=============================================================================
 
Total download size: 13 M

Note: [*] = 10 M of this is Perl, which is a common package between yum installs, could be already installed after another package.
-------------\\ needs updating \\

Finish installation of tool.

wget http://compcache.googlecode.com/files/compcache-0.3.tar.gz
tar xzf compcache-0.3.tar.gz
cd compcache-0.3
make
./use_compcache.sh


References

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