Mongrel isn't and wasn't single-threaded. Rails was.

Given that the most common reason for sticking with MySQL is the maturity of InnoDB and the surrounding toolsets, and the ability to hire knowledge easily this sounds like an excellent development.

Have you tried to hire a competent MySQL DBA recently?

`man hier`

Wow. How would one go about discovering this?

`man man` leads you to `man -k "file system"` (or apropos, as mentioned), leads you to ...

apropos hierarchy

apropos 'file system'

Very cool - thanks for mentionning this !