Subject: Details after Load Peak was: OT: Performance of VM
To: pgsql-performance@lists.postgresql.org
References: <3bc54eb3-135d-692c-47e2-208189a350d7@thomas-guettler.de>
 <91fec1f8-d11d-2413-6b57-5310ab0e3b8a@a-kretschmer.de>
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Date: Tue, 6 Feb 2018 15:31:27 +0100
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Am 05.02.2018 um 14:26 schrieb Andreas Kretschmer:
> 
> 
> Am 05.02.2018 um 14:14 schrieb Thomas Güttler:
>> What do you suggest to get some reliable figures? 
> 
> sar is often recommended, see https://blog.2ndquadrant.com/in-the-defense-of-sar/.
> 
> Can you exclude other reasons like vacuum / vacuum freeze?

In the current case it was a problem in the hypervisor.

But I want to be prepared for the next time.

The tool sar looks good. This way I can generate a chart where I can see peaks. Nice.

.... But one thing is still unclear. Imagine I see a peak in the chart. The peak
was some hours ago. AFAIK sar has only the aggregated numbers.

But I need to know details if I want to answer the question "Why?". The peak
has gone and ps/top/iotop don't help me anymore.

Any idea?

Regards,
   Thomas Güttler


-- 
Thomas Guettler http://www.thomas-guettler.de/
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