Re: WIP: dynahash replacement for buffer table

On Tue, Oct 14, 2014 at 8:38 PM, Andres Freund <andres(at)2ndquadrant(dot)com>
wrote:
>
> On 2014-10-14 20:30:45 +0530, Amit Kapila wrote:
> > On Tue, Oct 14, 2014 at 7:55 PM, Andres Freund <andres(at)2ndquadrant(dot)com>
> > wrote:
> > >
> > > On 2014-10-14 09:30:58 -0400, Robert Haas wrote:
> > > > A few years ago I started working on a concurrent hash table for
> > > > PostgreSQL. The hash table part of it worked, but I never did
> > > > anything with it, really. Amit mentioned to me earlier this week
that
> > > > he was seeing contention inside the dynahash machinery, which
inspired
> > > > me to go back and update the patch.
> > >
> > > Interestingly I've benchmarked similar loads, even on the same machine
> > > as Amit,
> >
> > There is one catch here, for these profiles I am using Power-8 m/c
> > and the load is slightly higher (5000 scale factor).
>
> Ah, right. I don't think the scale factor changes much, but the
> different architecture certainly does. As I said elsewhere, I would not
> believe these profiles much until they're actually done with optimized
> code...

Today, that m/c is not accessible, so will take a day or so to get the
optimized profiles and will post it once I am able to take the same.

With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com