On 8/27/14, 1:38 AM, Andres Freund wrote:
>> It occurs to me that it'd also be nice to have some
>> >stats available on how this is performing; perhaps a dtrace probe for
>> >whenever we overflow to the hash table, and one that shows maximum
>> >usage for a statement? (Presumably that's not much extra code or
>> >overhead...)
> I don't use dtrace, so*I* won't do that. Personally I just dynamically
> add probes using "perf probe" when I need to track something like this.
Yeah, I didn't mean dtrace directly; don't we have some macro that equates to dtrace or perf-probe depending on
architecture?
> I don't see how you could track maximum usage without more
> compliations/slowdowns than warranted.
I was thinking we'd only show maximum if we overflowed, but maybe it's still too much overhead in that case.
In any case, I was thinking this would be trivial to add now, but if it's not then someone can do it when there's
actualneed.
--
Jim C. Nasby, Data Architect jim@nasby.net
512.569.9461 (cell) http://jim.nasby.net