On 16 March 2011 20:59, Garrett Cooper <gcoo...@freebsd.org> wrote: > On Wed, Mar 16, 2011 at 12:51 PM, Ivan Voras <ivo...@freebsd.org> wrote: >> On 16 March 2011 18:46, Roman Divacky <rdiva...@freebsd.org> wrote: >>> >>> On Wed, Mar 16, 2011 at 04:22:59PM +0000, Ivan Voras wrote: >>> > Author: ivoras >>> > Date: Wed Mar 16 16:22:59 2011 >>> > New Revision: 219699 >>> > URL: http://svn.freebsd.org/changeset/base/219699 >>> > >>> > Log: >>> > The hardware has caught up; improvements are now observed even at 128, >>> > but stay conservative and bump read_max to "only" 64 (it will probably >>> > be >>> > a good idea to increase this to 128 after the next major release). >>> >>> how did you measure this? >> >> Specifically for this commit: my desktop 2xSATA 7200 RPM drives, >> gmirror, single read "dd" stream, bs=1m. (Are there any ready read >> multi-stream read tests which are not trivial i.e. they start from >> different positions in the file?) > > Would be interesting to see how well things work with the new > geom_raid bits and with other drives (SAS, SCSI).
Yes, I'd be interested in that; I'll try it when I get the chance to test new hardware. For now, there's a report (which actually inspired me to retest and commit this) from someone who tried this on 2x 15k RPM SAS drives, with much better results using read_max=128 (thread "gmirror performance" on freebsd-fs@). I estimate that because his drives were 15kRPM from the start, the improvement isn't as drastic going from 8 to 128 as on these SATA drives I tested on (faster seeks). He went from ~~ 195 MB/s to ~~ 258 MB/s while I go from ~~ 50 MB/s to ~~ 140 MB/s. _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
