[Gllug] memory usage in linux

Chris Bell chrisbell at overview.demon.co.uk
Wed Aug 28 00:17:21 UTC 2002


On Tue 27 Aug, Pavel Bradut Boghita wrote:
> 
> This is my first posting on this list so greetings to you all.
> I have been using linux for over a year, but only recently started to learn 
> more about the system as such. By running 'top' I've noticed that a great 
> deal of memory is being used. I had 128 M of memory and the system was using 
> most of it. Now I have 384 and 226 is being used. I understand that this is 
> normal, but I haven't yet understood what hides behind this high memory 
> usage. Could someone be kind enough to give me a short explanation or maybe 
> point to some useful resource that they may know of ?
> 
> Thanks.
> 
> Bradut
> 
   One of the duties of the operating system is to ensure best use of the
memory available. There are many reasons for use of memory, including input
and output buffers, declared variables, kernel modules, proceedures and
functions running in the background, and data maps such as directory and
file locations. Each active process would use some memory. The kernel also
has access control and logging duties.
   A large chunk would be for library functions retrieved for use from disc,
with the ones most frequently used being held in memory for as long as
possible to minimise the time spent accessing the discs. The kernel would
also expect to find swap files totalling at least twice the available RAM
memory for its own use.
   It is not neccessary to load a complete file into memory in order to view
or edit just a part of it, but then an edited section of a file may be held
in memory to avoid repeated disc accesses, and only re-saved to disc when
the processor is less busy.

-- 
Chris Bell


-- 
Gllug mailing list  -  Gllug at linux.co.uk
http://list.ftech.net/mailman/listinfo/gllug




More information about the GLLUG mailing list