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From:Gary W. Smith Date:March 2 2007 4:29am
Subject:RE: Replication performance questions
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> The table is MyISAM.  I searched on google a bit for info on slow
> updates with MyISAM and didn't really hit it on the nose.  Can I ask
> you to elaborate?
> 

In /etc/my.cnf try adding:

long_query_time = 1
log-slow-queries=/var/lib/mysql/mysql-slow.log

Restart and then watch the file.  If a anything pop's up, do an EXPLAIN
on the SQL statement and see what might be slowing it down.  This helped
me when I was debugging a join between two tables with a where clause
between the two on a non-indexed field (with 100k rows in one, 30k rows
in another).  It wasn't too slow but I was able to turn the 5+ second
response to around .2 seconds on one of our test servers.  My dev
environment that I'm testing my 50M row database on is a P4 HT
workstation running under xen DomU (with 1gb of ram in the DomU).  At
first I thought all my sluggish responses were because of hardware but
low and behold, it was just in need of some good indexes.  With that
said, don't go index crazy.

If that fails and nothing else seems to help, add lots of ram and cpu's
:).  

Hope that helps.


Thread
Replication performance questionsRoss Vandegrift2 Mar
  • RE: Replication performance questionsGary W. Smith2 Mar
    • RE: Replication performance questionsGary W. Smith2 Mar
    • Re: Replication performance questionsRoss Vandegrift2 Mar
      • RE: Replication performance questionsGary W. Smith2 Mar
        • Re: Replication performance questionsRoss Vandegrift2 Mar
          • RE: Replication performance questionsGary W. Smith2 Mar
            • Re: Replication performance questionsRoss Vandegrift6 Mar
              • Re: Replication performance questionsAtle Veka9 Mar