Re: testing ProcArrayLock patches

On Fri, Nov 18, 2011 at 6:46 PM, Kevin Grittner
<Kevin.Grittner@wicourts.gov> wrote:
>>> tps = 21946.961196 (including connections establishing)
>>> tps = 22911.873227 (including connections establishing)
>>>
>>> For write transactions, that seems pretty respectable.
>>
>> Very.  What do you get without the patch?
>
> [quick runs a couple tests that way]
>
> Single run with -M simple:
>
> tps = 23018.314292 (including connections establishing)
>
> Single run with -M prepared:
>
> tps = 27910.621044 (including connections establishing)
>
> So, the patch appears to hinder performance in this environment,
> although certainty is quite low with so few samples.  I'll schedule
> a spectrum of runs before I leave this evening (very soon).

Hmm.  There's obviously something that's different in your environment
or configuration from what I tested, but I don't know what it is.  The
fact that your scale factor is larger than shared_buffers might
matter; or Intel vs. AMD.  Or maybe you're running with
synchronous_commit=on?

--
Robert Haas
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