That might be true Andrew, but the thing is, my MySQL PS is crawling right now (check my website if you don't believe it). I have 1 GB of memory allocated to the MySQL server, but the innodb_buffer_pool_size is set at a pultry 8 MB!
All of my tables are innodb, some them are very big, and some of the queries are doing a lot of work. The default setting for this is 256 MB (32x DreamHost's setting!).
There was a suggestion to increase this made in December (not from me, but at least it proves I'm not the only person to mention this).
This is from the guy that wrote MySQL Performance book:
I've got a huge amount of memory available when I look at the graphs on the Manage VPS Resources tab, but when I look at running queries, I'm seeing queries being copied to temp tables on disk. I've asked support for several configuration settings to be tweaked, but the response was that they wouldn't/couldn't do it(!)
The slow query log frquently shows a simple SELECT * FROM SomeSmallTable taking over a minute to run!! I'm on the verge of moving my site elsewhere, if moving MySQL to a Web PS is a bad idea, as I can't keep the site here if it's going to continue to perform like this.
It's very annoying giving all this memory (and spending a lot of $$$), only for the config to be set so out of step with my requirements. It's supposed to be a private server, yet we can't seem to change anything on it.