Multiple copies of MySQL on a single server
 

Does anyone know if this would help the searching issues on a larger board? My load is reasonable until a dozen people try to search at the same time. I was hoping that this might help the table locking and keep me from having to get a new server (or set of servers) until next year.

If you think it would help, does anyone know how to go about installing a second copy of mysql?

Im not quite sure, but it would be better if you used multiple DB's and used just one for searches. Because the load will double if you install multiple instances of mysql in a single box.

my 2 cents.
If Im wrong just let me know.

Don't install multiple db servers on the same machine...it won't do anything, at all. Do a quick search on these forums for "big boards" or slow search. You should get a few good tips on speeding that up.

Well, that's not exactly true - having 2 post tables, even if they're on the same server, and only search one of them will reduce table locking and may reduce loads overall associated with that. However, it's better to offload search to a separate slave server.

Separate slave server and separate image server (to help main server)

my 2 cents :)

That's what I thought. The box I have seems to be more than powerful enough to handle the sites as long as there is little-to-no table locking.

I have a second server "available" (for testing, not permanent use) and I tried setting up a slave server a month or so ago but it didn't go well. For one, no "CREATE TABLE", "ALTER TABLE", or "DROP TABLE" statements were replicated to the slave. That means that any time I upgraded vBulletin or made some other DB change that those changes would not be replicated and the slave would break. Next, I had problems with the connection between the servers being dropped. Finally, when it did work, the site actually seemed slower for general use (but without the load peaks from searches).

You can set it up so that only certain tables need to be replicated, but this involves a recode of search.php.