From: | Robert Haas <robertmhaas(at)gmail(dot)com> |
---|---|
To: | Jeff Janes <jeff(dot)janes(at)gmail(dot)com> |
Cc: | pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: wal_buffers, redux |
Date: | 2012-03-12 17:55:26 |
Message-ID: | CA+TgmoZwdieQoSRn=riLs0uJJF3EefkQD2cA8ZDoXiA7esvkYA@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Mon, Mar 12, 2012 at 12:32 PM, Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:
> On Nate Boley's machine, the difference was ~100% increase rather than
> ~10%.
Oh, right. I had forgotten how dramatic the changes were in those
test runs. I guess I should be happy that the absolute numbers on
this machine were as high as they were. This machine seems to be
beating that one on every metric.
> Do you think the difference is in the CPU architecture, or the
> IO subsystem?
That is an excellent question. I tried looking at vmstat output, but
a funny thing kept happening: periodically, the iowait column would
show a gigantic negative number instead of a number between 0 and 100.
This makes me a little chary of believing any of it. Even if I did,
I'm not sure that would fully answer the question. So I guess the
short answer is that I don't know, and I'm not even sure how I might
go about figuring it out. Any ideas?
> Also, do you have the latency numbers?
Not at the moment, but I'll generate them.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
From | Date | Subject | |
---|---|---|---|
Next Message | Jaime Casanova | 2012-03-12 18:04:28 | Re: Partitioning triggers doc patch |
Previous Message | Simon Riggs | 2012-03-12 17:50:11 | Re: foreign key locks, 2nd attempt |