Memory load

[Cian Cullinan]

On 6/2/05, Ignacio Gómez <igomezu at gmail.com> wrote:
> I want to know how Linux manages the Memory. My server has 2gb of Ram
> Memory.  I see that my server always loads more than  2 GB is this
> normal?
> when my server is idle is the same.
> 

The Linux VM does it's best to use almost all of your systems RAM.
Thought about the right way this is a good thing though because unused
RAM is doing you and your system no good. Basically the Linux VM
caches very aggressively. What you want to look at is not the amount
of " free" memory (this should always be small except for a short
while after the system boots) but the amount of "cached" memory. This
is where the Linux kernel keeps information that has been accessed at
some stage and might be needed again. If it is needed again then the
it only has to be fetched from RAM, not from the hard disk, and if
memory is needed for some new application then it can be written to
disk to make room.
So in your example below, only about 1/8 of your systems memory is
actively being used, the rest is just cached info.
  For a straightforward explanation of the Linux VM (and why we need
swap space), check out:
http://sourcefrog.net/weblog/software/linux-kernel/swap.html

Cian