On Mon, 2010-02-08 at 09:49 -0800, Josh Berkus wrote: > FWIW, back when deadline was first introduced Mark Wong did some tests > and found Deadline to be the fastest of 4 on DBT2 ... but only by about > 5%. If the read vs. checkpoint analysis is correct, what was happening > is the penalty for checkpoints on deadline was almost wiping out the > advantage for reads, but not quite. I also did some tests when I was putting together my Synchronized Scan benchmarks: http://j-davis.com/postgresql/83v82_scans.html CFQ was so slow that I didn't include it in the results at all. The tests weren't intended to compare schedulers, so I did most of the tests with anticipatory (at least the ones on linux; I also tested freebsd). However, I have some raw data from the tests I did run with CFQ: http://j-davis.com/postgresql/results/ They will take some interpretation (again, not intended as scheduler benchmarks). The server was modified to record a log message every N page accesses. Regards, Jeff Davis -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
