Re: Scaling shared buffer eviction

On 2014-09-25 10:42:29 -0400, Robert Haas wrote:
> On Thu, Sep 25, 2014 at 10:24 AM, Andres Freund <andres@2ndquadrant.com> wrote:
> > On 2014-09-25 10:22:47 -0400, Robert Haas wrote:
> >> On Thu, Sep 25, 2014 at 10:14 AM, Andres Freund <andres@2ndquadrant.com> wrote:
> >> > That leads me to wonder: Have you measured different, lower, number of
> >> > buffer mapping locks? 128 locks is, if we'd as we should align them
> >> > properly, 8KB of memory. Common L1 cache sizes are around 32k...
> >>
> >> Amit has some results upthread showing 64 being good, but not as good
> >> as 128.  I haven't verified that myself, but have no reason to doubt
> >> it.
> >
> > How about you push the spinlock change and I crosscheck the partition
> > number on a multi socket x86 machine? Seems worthwile to make sure that
> > it doesn't cause problems on x86. I seriously doubt it'll, but ...
> 
> OK.

Given that the results look good, do you plan to push this?

Greetings,

Andres Freund

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