"David Magda" <dma...@ee.ryerson.ca> writes: > On Tue, June 16, 2009 15:32, Kyle McDonald wrote: > >> So the cache saves not only the time to access the disk but also >> the CPU time to decompress. Given this, I think it could be a big >> win. > > Unless you're in GIMP working on JPEGs, or doing some kind of MPEG > video editing--or ripping audio (MP3 / AAC / FLAC) stuff. All of > which are probably some of the largest files in most people's > homedirs nowadays.
indeed. I think only programmers will see any substantial benefit from compression, since both the code itself and the object files generated are easily compressible. > 1 GB of e-mail is a lot (probably my entire personal mail collection > for a decade) and will compress well; 1 GB of audio files is > nothing, and won't compress at all. > > Perhaps compressing /usr could be handy, but why bother enabling > compression if the majority (by volume) of user data won't do > anything but burn CPU? > > So the correct answer on whether compression should be enabled by > default is "it depends". (IMHO :) ) I'd be interested to see benchmarks on MySQL/PostgreSQL performance with compression enabled. my *guess* would be it isn't beneficial since they usually do small reads and writes, and there is little gain in reading 4 KiB instead of 8 KiB. what other uses cases can benefit from compression? -- Kjetil T. Homme Redpill Linpro AS - Changing the game _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
