On Tue, May 16, 2006 at 12:27:42PM -0400, Andrew Dunstan wrote: > Rod Taylor wrote: > >>I habitually turn off all compression on my Windows boxes, because it's > >>a performance hit in my experience. Disk is cheap ... > >> > > > >Disk storage is cheap. Disk bandwidth or throughput is very expensive.
Hey, that's my line! :P > Sure, but in my experience using Windows File System compression is not > a win here. Presumably if it were an unqualified win they would have it > turned on everywhere. The fact that there's an option is a good > indication that it isn't in many cases. It is most commonly used for > files like executables that are in effect read-only - but that doesn't > help us. The issue with filesystem level compression is that it has to support things like random access, which isn't needed for on-disk sorting (not sure about other things like hashing, etc). In any case, my curiousity is aroused, so I'm currently benchmarking pgbench on both a compressed and uncompressed $PGDATA/base. I'll also do some benchmarks with pg_tmp compressed. Does anyone have time to hack some kind of compression into the on-disk sort code just to get some benchmark numbers? Unfortunately, doing so is beyond my meager C abilitiy... -- Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED] Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461 ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
