On Tue, Aug 30, 2011 at 12:54 AM, Florian Weimer <fweimer@bfk.de> wrote:
> * Scott Marlowe:
>
>> On a machine with lots of memory, I've run into pathological behaviour
>> with both the RHEL 5 and Ubuntu 10.04 kernels where the kswapd starts
>> eating up CPU and swap io like mad, while doing essentially nothing.
>> Setting swappiness to 0 delayed this behaviour but did not stop it.
>> Given that I'm on a machine with 128G ram, I just put "/sbin/swapoff
>> -a" in /etc/rc.local and viola, problem solved.
>
> Was this NUMA machine? Some older kernels can only migrate pages
> between nodes through swap.
48 core AMD Magny Cours. I also had to turn off zone reclaim mode on
it or it would slow to a crawl as the OS started to cache more and
more data.