Re: PostgreSQL pgbench performance regression in 2.6.23+

From: Greg Smith
Date: Fri May 23 2008 - 19:21:07 EST

On Fri, 23 May 2008, Mike Galbraith wrote:

It was running SCHED_BATCH, needed features=0 as well to achieve O(1) batch performance.

I figured out how to run pgbench with chrt in order to get SCHED_BATCH behavior, but I don't understand what you mean by features=0 here. Since I didn't see the same magnitude of different just using batch that seems important, where does that get set at?

I'm also curious what hardware your results are coming from, to fit them into my larger pgbench results context space.

Got my 4-core system back on-line again today (found some bad RAM) and wanted to try another round of tests on that. Looks like you've defined 5 test sets I should replicate:

2.6.22, batch
2.6.26.git, batch
2.6.26.git, batch + se.load.weight patch

Should I still be trying Peter's se.waker patch as well in this mix somewhere?

* Greg Smith gsmith@xxxxxxxxxxxxx Baltimore, MD
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