Marshal.dump oddity: Marshal.dump is squirrelly with ActiveRecord objects in Rails. If you dump multiple AR instances that represent the same entity but have different in memory states, the serialization will basically “collapse” those two instances to a single instance. This means you’ll lose changes to one of the instances. Anyone out there know why?
Disabling system pagefile in XP on Parallels: If you disable the Page File in XP it will run super fast in Parallels. This makes sense when you think about it; there are two operating systems on the machine that are trying to manage memory. Both swapping out to disk. Assuming the XP instance has enough RAM (and you’re not running that many processes), turn off paging in XP for a big speed boost.