Re: Repeated semop calls

On 2014-06-27 10:51:20 -0700, Jeff Janes wrote:
> On Thu, Jun 26, 2014 at 1:03 PM, Anand Kumar, Karthik
> > Samples: 33K of event 'cycles', Event count (approx.): 20693251070
> >  26.16%  postmaster  postgres               [.] 0x0000000000188450
> >  21.13%  postmaster  postgres               [.] hash_search_with_hash_value
> >  10.47%  postmaster  postgres               [.] heap_page_prune_opt
> >   4.21%  postmaster  postgres               [.] LWLockAcquire
> >   3.71%  postmaster  postgres               [.] slot_getattr
> >   1.97%  postmaster  postgres               [.] HeapTupleSatisfiesMVCC
>
> If it is what I am guessing at, then the top anonymous address is
> probably coming from LWLockAcquire, and those are coming from
> HeapTupleSatisfiesMVCC.  I don't know how to verify that, though.

Recompile postgres with -fno-omit-frame-pointers and use perf record -g.

Greetings,

Andres Freund

--
 Andres Freund                       http://www.2ndQuadrant.com/
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