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Re: Help

yufufi <yufufi@yahoo.com> writes:
> Hi,

Hi Furkan,

You need to keep in mind that X uses a lot of memory. If you can hear
your disk writing during these stalls, it may be that your system is
using the swap partition as extra memory.

For example, say you're using mozilla for X but then switch to another
application (that is already open). If you notice a stall, it most
likely is that Linux is having to put core memory (the physical memory
chips [RAM]) onto the swap partition, as well as moving memory on the
swap partition into core.

A good way to diagnosis this in X is to pull up an xterm and run the
program 'top'. Top displays the processes currently running on your
system (atleast the ones that will fit upon the screen). More
importantly, though, for your scenerio is that it mentions memory
information at the top of the screen, such as:

Mem:  110304K av,  90716K used,  19588K free,      0K shrd,  15704K buff
Swap: 124952K av,  13816K used, 111136K free                 44456K cached

The first part is the core (RAM) memory and the second is the extended
memory using a swap partition. From this example, you can see that on
this particular machine there is about 110M available of core memory
and about 124M of swap space available, giving me rougly 234M of
virtual memory.

What's important to understand is that the memory stored upon the swap
partition is *much* slower than the core memory. In the above example,
I've gone 13M into swap space; so, if this snapshot of memory is from
typical usage of the machine, it lets me know that if I want to
increase the system's overall speed, I should add about 13M of core
memory (chips/RAM).

How does this "increase the system's speed?" Because the kernel is not
having to load memory pages to and from the swap space. The less this
occurs, the greater the overall speed of the system. (Note: swapping
memory pages in and out by the memory manager is termed as
'thrashing'; it is best to minimize this).

So, based on what you've said, I recommend you investigate your memory
situation using top as described above. If indeed you see a large
number of used space in your swap partition(s), you should increase
the RAM memory of your machine or just get used to it.

Regards, Elizabeth

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