Re: pgbench cpu overhead (was Re: lazy vxid locks, v1)

Jeff Janes <jeff(dot)janes(at)gmail(dot)com> writes:
> How was this profile generated? I get a similar profile using
> --enable-profiling and gprof, but I find it not believable. The
> complete absence of any calls to libpq is not credible. I don't know
> about your profiler, but with gprof they should be listed in the call
> graph even if they take a negligible amount of time. So I think
> pgbench is linking to libpq libraries that do not themselves support
> profiling (I have no idea how that could happen though). If the calls
> graphs are not getting recorded correctly, surely the timing can't be
> reliable either.

Last I checked, gprof simply does not work for shared libraries on
Linux --- is that what you're testing on? If so, try oprofile or
some other Linux-specific solution.

regards, tom lane