[CentOS] IO causing major performance issues

Les Mikesell lesmikesell at gmail.com
Thu Nov 15 22:59:42 UTC 2007

Ross S. W. Walker wrote:
> Yes, IO starvation can occur under heavy load.

But it should stall the process needing to write, not everything.

> Don't put database temp tables on system disks (or data tables for that matter).
> How much memory do you have in this box and how big does the temp directory
> usage get?
> Why I ask is you could create a tempfs and have mysql use that, just make sure
> you have enough memory that you can spare X (whatever your temp table usage is)
> for a cache filesystem.
> You would also notice a dramatic speed increase in MySQL.

I'm not sure the needed temp table space is predictable.  I've seen 
mysql be pretty dumb about how it does a select that joins several tables.

   Les Mikesell
    lesmikesell at gmail.com

More information about the CentOS mailing list