In article <7b9699030501160510642be9af@mail.gmail.com>,
	Mark Thomas <thomas.s.mark@gmail.com> writes:
> When runing top I see the line;
> "Memory: 522M Act, 38M Inact, 380K Wired, 12M Exec, 325M File, 352M Free"
> what does the "325M File" stand for?

Oh, I know that one.  It's the amount used by the Universal Buffer Cache, 
i.e. the file cache.  When you write a file "to disk", it's still in the 
file cache for a while, so you can read it back quickly without actually 
touching the disk. It's called "universal" because there used to be many 
caches for individual file systems and other things, but now they can all 
share. It's also a "buffer", so that the driver can re-order writes.

While we're on the subject, I've always wondered why "Active" isn't quite 
the sum of any of the other numbers. If anyone knows, I'd love to hear an 
explanation for that.


Frederick