Re: Recommended Swap space - Mailing list pgsql-performance

From Scott Marlowe
Subject Re: Recommended Swap space
Date
Msg-id CAOR=d=2LAOYhbV-ThcB5U9UwLP08dfqnjYkMvr+Zp5Kp_bEwxA@mail.gmail.com
Whole thread Raw
In response to Re: Recommended Swap space  (Claudio Freire <klaussfreire@gmail.com>)
List pgsql-performance
No, I've had it happen with NUMA turned off. The NUMA issues are with zone_reclaim_mode.  If you have it set to 1 (default on a lot of big machines) it can cause serious problems with performance as well.


On Fri, Apr 12, 2013 at 3:21 PM, Claudio Freire <klaussfreire@gmail.com> wrote:
On Fri, Apr 12, 2013 at 6:15 PM, Scott Marlowe <scott.marlowe@gmail.com> wrote:
> The really messed up bit is that the problems with the kswapd won't show up
> for weeks, months, or sometimes even longer. The symptoms of a kswapd
> problem is that swap is mostly full, but there's LOTS of free memory /
> kernel cache, and the kswapd is busily swapping in / out.  Page faults
> skyrocket and the problem can last for a few minutes or a few hours, then
> clear up and not occur again for a long time.

Isn't that a NUMA issue?



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