Re: measuring spinning

On Wed, Jan 11, 2012 at 8:48 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> I've had cause, a few times this development cycle, to want to measure
> the amount of spinning on each lwlock in the system.  To that end,
> I've found the attached patch useful.  Note that if you don't define
> LWLOCK_STATS, this changes nothing except that the return value from
> s_lock becomes int rather than void.  If you do define LWLOCK_STATS,
> then LWLockAcquire() counts the number of pg_usleep() calls that are
> required to acquire each LWLock, in addition to the other statistics.
> Since this has come up for me a few times now, I'd like to proposing
> including it in core.

Well, this fell through the cracks, because I forgot to add it to the
January CommitFest.  Here it is again, rebased.

--
Robert Haas
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