5 messages in com.mysql.lists.packagersRe: -DBIG_JOINS
FromSent OnAttachments
Christian Hammers22 Jul 2004 14:35 
Lenz Grimmer22 Jul 2004 16:33 
Christian Hammers23 Jul 2004 09:37 
Lenz Grimmer27 Jul 2004 01:19 
Lenz Grimmer27 Jul 2004 01:21 
Subject:Re: -DBIG_JOINS
From:Lenz Grimmer (le@mysql.com)
Date:07/27/2004 01:21:51 AM
List:com.mysql.lists.packagers

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Hi,

On Thu, 22 Jul 2004, Christian Hammers wrote:

I've just got the hint to build my packages with this option. Looks good (enabling ~64 instead of ~32 tables in a join) but I wonder why it isn't the default. Are there major performance drawbacks?

Here is a reply I got:

[SNIP] On 32-bit systems both BIG_JOINS and BIG_TABLES end up using 64-bit integers instead of 32-bit ones.

That makes things slower.

How much ???

Depends on the queries ... 5 % ?? [SNIP]

So it's hard to tell - we have not yet benchmarked these two configurations against each other. It may make sense to enable this option for the "Max" binary only (as we do it) - if you have a "max" binary at all, that is.

Bye, LenZ - -- Lenz Grimmer <le@mysql.com> Senior Production Engineer MySQL GmbH, http://www.mysql.de/ Hamburg, Germany -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) Comment: For info see http://quantumlab.net/pine_privacy_guard/

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