Re: Making hash indexes worthwhile

Jeff Janes <jeff.janes@gmail.com> writes:
> Do you know why that should be?  I've done some work with gprof, and
> the results are pretty suspect, because the total gprof time adds up
> to only about 1/3 of the total time the backend spends on CPU
> (according to "top"), and I don't know where the unaccounted for time
> is going.

Are you sure that gprof is delivering trustworthy numbers at all?
I've seen cases where it was consistently mis-timing things.
https://bugzilla.redhat.com/show_bug.cgi?id=151763
Admittedly that was an old Linux version, but ...
        regards, tom lane