| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Andrew Dunstan <andrew(at)dunslane(dot)net> |
| Cc: | PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: larger shared buffers slows down cluster |
| Date: | 2012-08-22 21:00:56 |
| Message-ID: | 22076.1345669256@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> Now running:
> cluster bar using bar_abcde;
> appears to be very sensitive to the shared buffers setting. In an amazon
> very large memory instance (64GB) and PostgreSQL 9.1.4, I observed the
> following timings:
> Shared Buffers Time
> 48Gb 2058ms
> 8Gb 372ms
> 1gb 67ms
DropRelFileNodeBuffers, perhaps? See recent commits to reduce the cost
of that for large shared_buffers, notably
e8d029a30b5a5fb74b848a8697b1dfa3f66d9697 and
ece01aae479227d9836294b287d872c5a6146a11
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Jeff Janes | 2012-08-22 21:19:25 | Re: larger shared buffers slows down cluster |
| Previous Message | Andrew Dunstan | 2012-08-22 20:48:21 | larger shared buffers slows down cluster |