Re: Server stalls, all CPU 100% system time

From: Andre <pg(at)darix(dot)de>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Server stalls, all CPU 100% system time
Date: 2013-02-26 12:53:17
Message-ID: 512CB03D.6080506@darix.de
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On 25/02/2013 12:45 AM, Tom Lane wrote:
> Odd. I wonder if you are seeing some variant of the old context swap storm problem. The "99.8% system time" reading is suggestive but hardly conclusive. Does top's report of context swap rate go to the moon? It would be interesting to strace a few of the server processes while one of these events is happening, too. regards, tom lane

I used vmstat to look at the context swaps, they were around 5k and 15k interrupts per second.
I thought that it was to many interrupts and after a bit of search a website mentioned that the network card driver could cause that. After updating kernel and the driver the stalling is not reproducible any more.

Weird enough, when I load test the server now I have 35k interrupts and 250k context switches, but no problems at all.

Thanks for pointing me into the right direction.

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