Carlos,
> We've migrated one of our servers from pg 7.4 to 8.1 and from times to
> times (4 hours) the server start doing a lot of context switching and all
> transactions become very slow.
>
> The average context switching for this server as vmstat shows is 1 but when
> the problem occurs it goes
On Tue, Dec 06, 2005 at 03:01:02PM -0600, Brandon Metcalf wrote:
> We're running a dual Xeon machine with hyperthreading enabled and
> PostgreSQL 8.0.3.
The two single most important things that will help you with high rates of
context switching:
- Turn off hyperthreading.
- Upgrade to 8.1.
t == [EMAIL PROTECTED] writes:
t> "Brandon Metcalf" <[EMAIL PROTECTED]> writes:
t> > We've been tuning the kernel (2.4 SMP flavor) and have improved
t> > performance quite a bit. I'm now wondering if turning off HT will
t> > improve performance even more. Based on the vmstat output below, is
"Brandon Metcalf" <[EMAIL PROTECTED]> writes:
> We've been tuning the kernel (2.4 SMP flavor) and have improved
> performance quite a bit. I'm now wondering if turning off HT will
> improve performance even more. Based on the vmstat output below, is
> the context switching typical or too high?
G
"Sailer, Denis (YBUSA-CDR)" <[EMAIL PROTECTED]> writes:
> http://archives.postgresql.org/pgsql-performance/2004-04/msg00280.php
> The last messages on this subject are from April of 2005. Has there
> been any successful ways to significantly reduce the impact this has to
> multi-processing?
CVS
FWIW, I'm seeing this with a client at the moment. 40-60k CS per second
on Dual 3.2GHz.
There are plenty of other issues we're dealing with, but this is
obviously
disconcerting...
On 19 Jul 2005, at 19:23, Sailer, Denis (YBUSA-CDR) wrote:
The thread below has the test case that we were abl
Jellej,
> Is context switching problem resolved in 8.0?
>
> Can I drop in another Xeon?
Nope, not solved yet. However, it only affects certain data access patterns.
So don't use it as a reason not to go multi-processor.
--
--Josh
Josh Berkus
Aglio Database Solutions
San Francisco
Hello,
Is context switching problem resolved in 8.0?
Can I drop in another Xeon?
Thanks,
Jelle
On Wed, 2 Jun 2004, Josh Berkus wrote:
> Folks,
>
> I've been testing varying SPINS_PER_DELAY in a client's installation of
> PostgreSQL against a copy of a production database, to test varying t
