WordPress MU

I'm having some issues with my installation of WPMU at blogs.utexas.edu. My MySQL DBA is telling me that he is getting reports of "Lock Contention Excessive". He says, that this means we have multiple queries competing for the same table or row. In this case I believe it may be at the table level seeing I have multiple MyISAM tables. MyISAM doesn't support row level locking. Out of 868 tables,I have nine MyISAM tables.

So my question is, how important is it that the following tables are MyISAM? What would happen if I let my DBA switch them to InnoDB?
+---------------------------+--------+------------------+
| TABLE_NAME | ENGINE |
+---------------------------+--------+
| sk2_blacklist | MyISAM |
| wp_1_sk2_logs | MyISAM |
| wp_1_sk2_spams | MyISAM |
| wp_26_sk2_logs | MyISAM |
| wp_26_sk2_spams | MyISAM |
| wp_4_sk2_logs | MyISAM |
| wp_4_sk2_spams | MyISAM |
| wp_firestats_pending_data | MyISAM |
| wp_spam | MyISAM |

Thanks for any advice you can give me,
Glenda (the goodwitch)

InnoDB. Absolutely.

I just realized, the title of my post is backwards...I'm wanting to know if it is okay to switch these tables from MyISAM to InnoDB.

Based on lugabyte's response, I believe it is safe (and a good idea) to switch these tables to InnoDB. I'll report back here if indeed this solves my problem.

Your whole DB can be switched to InnoDB :)

Well, your DBA wouldn't be saying it if it was junk. :)

InnoDB is a good choice in the right situation. If for nothing more than the recovery capabilities. While it is true that there is a negligible difference in read times as compared to MyISAM, if the amount of writes are even 15% of the total queries, you'll see improvement or at least not lose ground. More than that and the gains outweigh any potential downsides. Again, even for the recovery capabilities alone on large, important tables.

Your DBA may be aware of this, but if not, have him check out the 5.1 builds from the http://ourdelta.org/ site. They have the patches/fixes already in place, and run really well.

This is a very interesting topic. By default my WP install is sitting in MyIsam and I have wondered if moving some or all of the tables to InnoDB would be worth doing. I am certainly thinking about doing it for the montyspam tables