Apache::Singleton::Server got me thinking about Cache::Cache and locking again. if i'm going to have a server-global object, i am going to need to protect against multiple processes updating it simultaneously, right?
we've already talked about this in regards to sessions. most folks seem to feel that "last one wins" is sufficient for session data. but what about for objects for which this policy is not good enough? if locking is necessary in some instances, even if we can only contrive theoretical examples right now, how might it be done in a performant way, especially for objects that can be modified multiple times while handling a single request? seems like if you synchronized write access to the object and caused each process to update its local copy after each modification, you'd have a hell of a lot of serialization and deserialization going on in each request. thoughts?
