Re: [GENERAL] statistics collector process is thrashing my cpu

William Temperley wrote:
> On Thu, May 8, 2008 at 6:14 PM, Magnus Hagander <magnus@hagander.net>
> wrote:
> > William Temperley wrote:
> >> > >
> >> > > Any ideas why this might be happening, and how I can stop it?
> >> >
> >> > It'd be interesting to know what the stats collector is actually
> >> > doing. Could you, using Process Explorer or a debugger, get a
> >> > stack trace from that process while it's in the trashing state?
> >> >
> >> > //Magnus
> >> >
> >>
> >> Certainly, but I'll have to wait 'til it does it again, it doesn't
> >> happen all the time.
> >> What would you like to know from Process Explorer?
> >
> > Get the backtrace from hung process. Find the process in the list,
> > open it. Go to the tab "Threads", find the thread that's using a
> > lot of CPU (or at least has a lot of ocntext switchs), and click
> > the Stack button. That should give you a window with a backtrace.
> >
> > //Magnus
> >
>
> Ok, got the little blighter. Below are 4 stack traces taken at random
> times. Doesn't seem to be doing much I/O (16 reads and 167 other in 3
> hours). The memory usage seems to be static (3.7MB) even with high
> database usage (vacuum, read, update).

Hmm. They all show the same function, but it's not a function being
used in the stats collector. I think I missed a step in the
instructions - you need to download the symbols for the server (make
sure you get the same version!) and configure process explorer to use
those (IIRC, it can use detached symbols), then do the same things
again. Sorry for missing that in the first instructions!

//Magus

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