On Fri, Oct 3, 2014 at 5:51 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> I do think that the instrumentation data gathered by LWLOCK_STATS is
> useful - very useful.
Sure, quite useful.
But how about this comment:
/* * The LWLock stats will be updated within a critical section, which * requires allocating new hash entries.
Allocationswithin a critical * section are normally not allowed because running out of memory would * lead to a
PANIC,but LWLOCK_STATS is debugging code that's not normally * turned on in production, so that's an acceptable
risk.The hash entries * are small, so the risk of running out of memory is minimal in practice. */
> But it does have significant overhead.
I will say that it is a bit more than overhead for production use.
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