Re: dependency between numbers keywords and parser speed

2011/3/15 Robert Haas <robertmhaas@gmail.com>:
> 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.
>

When I tested it - all data was in memory, there was a minimal (near
zero IO) and I run read only test.

It doesn't mean, so parser is gratis, but my numbers doesn't show any
potential problem with 60 new keywords.

Pavel

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