To: "Greg Sabino Mullane" <greg@turnstep.com>
Cc: pgsql-interfaces@postgresql.org
Subject: Re: DBD::Pg performance bites compared to DBD::mysql?
References: <933399e2f40b843429889b52d6ebae8d@biglumber.com>
In-Reply-To: <933399e2f40b843429889b52d6ebae8d@biglumber.com>
From: Greg Stark <gsstark@mit.edu>
Organization: The Emacs Conspiracy; member since 1992
Date: 14 Jun 2005 02:44:28 -0400
Message-ID: <87u0k11lpv.fsf@stark.xeocode.com>
Lines: 25
User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii

"Greg Sabino Mullane" <greg@turnstep.com> writes:

> I still maintain the original test is brain-dead, however. :) It was
> testing for "insert speed" by basically doing this:
> 
> for (1..1000) {
>         $dbh->do("INSERT INTO testtable(a,b) VALUES (1,2)");
> }
> 
> It's as if the people who wrote it *cough*mysql*cough* never heard
> of prepare/execute and did not read the DBI docs.


Sure but wouldn't that show up as more time spent in the server in the parser
and planner? I thought Tom was complaining that it was spending too much time
in the client not waiting on server responses.

I wonder if Postgres is being bitten by doing lots of extra round trips. Maybe
the MySQL driver detects when there are no placeholders and no parameters and
uses a different protocol method that only requires a single round trip? Or
given your example maybe it even notices no result is needed and doesn't even
wait for a response?

-- 
greg