Re: Occasional giant spikes in CPU load

On Thu, 2010-06-24 at 17:50 -0700, Craig James wrote:
> I'm reviving this question because I never figured it out.  To summarize: At random intervals anywhere from a few
timesper hour to once or twice a day, we see a huge spike in CPU load that essentially brings the system to a halt for
upto a minute or two.  Previous answers focused on "what is it doing", i.e. is it really Postgres or something else? 
>
> Now the question has narrowed down to this: what could trigger EVERY postgres backend to do something at the same
time? See the attached output from "top -b", which shows what is happening during one of the CPU spikes. 

checkpoint causing IO Wait.

What does sar say about these times?

Joshua D. Drake


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