Re: dependency between numbers keywords and parser speed

On Mon, Mar 14, 2011 at 4:34 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Pavel Stehule <pavel.stehule@gmail.com> writes:
>> there was a discussion about impact of number of keyword for parser
>> speed. I did some synthetic tests and I didn't see any slowness on
>> pgbench when I increased a number of keywords.
>
> I don't see any particular reason to suppose that pgbench would be a
> good framework for stressing parsing speed.  The queries it issues
> are of trivial length.

I found that it was actually a fairly measurable component of the
select-only test when running with shared_buffers cranked up to a
reasonable value.  But it'd probably be a lot easier to measure on a
benchmark specifically targeted at the parser.

--
Robert Haas
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