On Sat, 9 Nov 2002, Hume Smith wrote:

> On Saturday November 9, 2002 10:51 am, you wrote:
> 
> > Tools like top or 'vmstat buf' will show you how much RAM is used to cache
> > file data and executables. This memory can be reclaimed for other use if
> > needed.
> 
> if one can decode it. eg WTF is `Wired'? What's diff Inact and Free? (top(1) 
> refers systat(1) which mentions `wired' but doesn't really explain it.)

IIRC...

"Wired" is memory that is wired into physical RAM and will never be
  swapped out. Most if this is probably kernel memory, but applications
  (run by root) can wire (limited amounts of) memory too using mlock(2).
"Active" is memory currently in use. It can be paged out if necessary,
  but isn't unless there's a real shortage of memory, since it's in use.
"Inactive" is memory that still holds valid data, but isn't currently
  in use, i.e. it acts as a cache of valid data that can be reused if
  the data is needed again, or reclaimed if there's a real shortage on
  memory.
"Free" simly means completely unused memory without any meaningful
  content.

"Available" memory is therefore a bit blurry, but should be something
not too far off from "Free" + "Inactive".


-- 
/ali
:wq