[lkml]   [2008]   [Oct]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 0/4] pending scheduler updates
On Wed, 2008-10-22 at 14:42 +0200, Ingo Molnar wrote:
> * Mike Galbraith <> wrote:
> > > > With that patch, pgsql+oltp scales perfectly.
> > >
> > > hm, tempting.
> >
> > I disagree. Postgres's scaling problem is trivially corrected by
> > twiddling knobs (or whatnot). [...]
> okay, then we need to document it a bit more: what knobs need twiddling
> to make it scale perfectly?

Twiddle sched_wakeup_granularity_ns or just turn FAIR_SLEEPERS off for
best pgsql+oltp scalability. Pgsql+oltp collapse is delicate. It
doesn't take much to send it one way or the other. Cut preempt a wee
bit, and it can snap right into shape.

I think we need to penalize sleepers a wee bit as load climbs in general
though, everybody begins to like preemption less as load increases.
Mysql+oltp improves as well, and it loves preempt at modest load.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2008-10-22 15:09    [W:0.026 / U:1.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site