As we have a high-traffic forums, we are having some performance issues, to the point nobody can enter our forums.

Analyzing with SHOW PROCESSLIST, we saw several locked tables, in particular skin_cache, sessions, and members.

Converted these three tables to InnoDB.

I don't have bad experience with InnoDB in the past, as on vBulletin it actually decreased performance.

However, it seems, at least for me, that selectively using InnoDB in a few tables (those listed above) performance really improved and solved our availability issues (at least for now).

I'd love to hear from other people who manage high-traffic forums and their experience with performance issues, table locking, and InnoDB usage.

Sessions would be even quicker if you made it a memory table.

Awesome tip, and I've just implemented it.

Facing performance issues again, now the table that has locking issues is content_cache_posts, and I'm altering it to InnoDB as well.

Awesome tip, and I've just implemented it.

Facing performance issues again, now the table that has locking issues is content_cache_posts, and I'm altering it to InnoDB as well.

Be aware though, MEMORY tables lose their content after a MySQL reboot, so don't many any other tables MEMORY.

I know! I set only sessions to be on memory!

wonder if mariadb or percona would work better for you.

wonder if mariadb or percona would work better for you.

Are these (mariadb and percona) different things? https://mariadb.com/kb/en/about-xtradb/

That's a real question -- in some places they are talked about as if they are different, but on that mariadb page it sounds like mariadb uses percona's innodb engine.

maria built upon the percona xtradb engine but adds more iirc.

iirc persona is closer to the mysql code.

Thanks, will take a look into that.

I know! I set only sessions to be on memory!

Just making it clear for anyone else that reads this in the future!