i found a very interesting page when browsing the web: http://linuxhelp.150m.com/resources/fs-benchmarks.htm

it benchmarks file systems on speed and disk space.

 

currently unraid uses Reiser3 (i think), which doesn't use compression.

well, reiser4 does support it and the result? -> file size is reduced by +- 70%.

 

so if u have 1 TB of data, u would normally need 1 TB of disk space

but with compression enabled u would only need 300 gig space for 1 TB of data.

 

any performance loss? well no.

on a 650mb file transfer without compression it took 148 seconds.

with compression it also took 148 second, but the disk space used is only 213mb

 

 

this would be really useful for unraid right? but is it possible?

I like the idea...but only as an option.  As I understand it, the only way to use a unRAID formatted drive under Windows -- say, in the case of multiple drives failures and there's some data you absolutely, positively wanted to get off -- is use an utility (http://p-nand-q.com/download/rfstool.html) to mount the file system.  I didn't see anything in the documentation, so I suspect it may not be able to handle compressed partitions.

It really depends on the type of files being stored. Most people store DVDs, Music, etc on their UnRaid servers. Those files are already highly compressed (mpeg,flac,etc) with optimized compression schemes. I doubt those would compress very much with Reiser4(which appears to use gzip/lzo).

It really depends on the type of files being stored. Most people store DVDs, Music, etc on their UnRaid servers. Those files are already highly compressed (mpeg,flac,etc) with optimized compression schemes. I doubt those would compress very much with Reiser4(which appears to use gzip/lzo).

Exactly... most media files would not be able to be compressed more than they already are, so it would add overhead for no actual gain.