Greg Smith wrote: > On Fri, 2 Jan 2009, Tom Lane wrote: > > > ISTM that you *should* be able to see an improvement on even > > single-spindle systems, due to better overlapping of CPU and I/O effort. > > The earlier synthetic tests I did: > > http://archives.postgresql.org/pgsql-hackers/2008-09/msg01401.php > > Showed a substantial speedup even in the single spindle case on a couple > of systems, but one didn't really seem to benefit. So we could theorize > that Robert's test system is more like that one. If someone can help out > with making a more formal test case showing this in action, I'll dig into > the details of what's different between that system and the others.
I think for an I/O-bound workload on a single drive system you would need a drive that did some kind of tagged queuing (reordering/grouping) of requests to see a benefit from the patch. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
