On 22/02/07, Peter Hardy <[EMAIL PROTECTED]> wrote:
I'm a little puzzled by this:
total used free shared buffers cached
Mem: 5005084 4816352 188732 0 156644 3165540
-/+ buffers/cache: 1494168 3510916
Swap: 1052616 1052616 0
Is this sort of usage normal? Filling a gigabyte of swap space while
just under 1.5GB of memory is going towards buffers seems odd to me. And
vmstat reports no usage of this swap space over a 15 minute period.
What sort of utilities are around to analyse swap space? I'd like to get
an idea of exactly what's using all of that memory.
You're running Linux, right?
As of.. urmm.. somewhere in the 2.4 series, or early in the 2.6
series, I forget where, the kernel developers decided to be very, very
aggressive about favoring buffers/cache over unrecently-used pages.
This can be really great on a system with not much ram where large
apps that you haven't used in a while (eg, OOo) will get swapped out
when they're not being used, to make lots of space to cache all the
pr0^H^H^Himages of your grandmother's birthday party that you're
scanning through agressively..
It's tuneable though, via /proc/sys/vm/swappiness. Quick google
search shows the below, from
http://beranger.org/index.php?article=1547 (which read, for a more
detailed explanation)
swappiness is a number between 0 and 100, representing how aggressive
the swap policy of the kernel is, or where is the balance between
swapping applications and freeing cache.
--
There is nothing more worthy of contempt than a man who quotes himself
- Zhasper, 2004
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