Re: [CentOS] IO causing major performance issues

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.