Where can I find documentation for server-side Groovy execution limits

To help us design and modularize our Groovy code, it would be helpful if there were a single concise documentation reference of server-side Groovy execution limits by the type of Groovy script.

For example, I have read somewhere there is a 30-second limit on Groovy Triggers. But what about object functions and global functions? Do they have different execution time limits? And how do these limits change based on the context from where they are called? (e.g., calling a global function from a trigger may still have the 30-second constraint).

Also, I have seen documentation somewhere else stating a limit of 500 objects/records (retrieved?) within a Groovy script. Is that limit for a Groovy Trigger? What about other Groovy execution contexts?