Re: [patch part 2] Re: [patch] Re: PostgreSQL pgbench performance regression in 2.6.23+

Mike Galbraith
2008-06-07T17:53:18Z

On Sat, 2008-06-07 at 18:12 +0200, Peter Zijlstra wrote:
> On Sat, 2008-06-07 at 16:54 +0200, Mike Galbraith wrote:
> > On Sat, 2008-06-07 at 15:08 +0200, Peter Zijlstra wrote:
> > > On Sat, 2008-06-07 at 13:38 +0200, Mike Galbraith wrote:
> > >
> > > Interesting.. Looks good.
> >
> > In that case it _might_ fly, so needs changelog and blame line.
>
> Just wondering, how much effect does the last_preempter stuff have?, it
> seems to me the minimum runtime check ought to throttle these wakeups
> quite a bit as well.

Without last_preempter, you'd have all tasks having a minimum runtime.
That would harm the single cpu starve.c testcase for sure, and anything
like it. I wanted to target this pretty accurately to 1:N type loads.

If you mean no trying to disperse preempters, I can test without it.

-Mike