Topic: Memory

[Jason]

I have gone into top on the server and I have 245Mb of my 256Mb of ram in buffer...Why is this..What is the buffer and what does it do...
Will it affect the performance of my server being so large..

It just keeps growing....

Concerned..

[Charlie Brady]

Jason wrote:

> I have gone into top on the server and I have 245Mb of my 256Mb
> of ram in buffer...Why is this..What is the buffer and what
> does it do... Will it affect the performance of my server being
> so large..
>
> It just keeps growing....

This is normal, and mentioned in the linux FAQ:

http://www.linuxdoc.org/FAQ/Linux-FAQ/x1855.html#AEN1949

You can learn a lot about linux by reading the documents at linuxdoc.org (but use a mirror somewhere close to you), and/or by reading a good linux book.

Regards

Charlie

[Charlie Brady]

Jason wrote:

> Why is this..What is the buffer and what does it do...

It is disk buffers - stuff waiting to go to disk, or stuff you read from disk, which it keeps in RAM in case you need it again.

> Will it affect the performance of my server being
> so large..

Yes, it will make your system faster.

> It just keeps growing....

It'll stop growing.

> Concerned..

Don't be.

Charlie

[Jason]

Thankyou you have alayed my fears..

Notice the new e-mail..I finally got my domain working...
Now onto building a web site...

Ohh the pain I have to learn how to make web pages now...

Jason..

[jason]

I have placed the line mem=256M in a config file somewhere...
Cant remember the discussion thread but it seems to have made a great deal of difference to the box...
It now runs with about 130Mb free all the time..

Much quuicker as well...

Thanks..

[Carl Enset]

Speaking as some one who runs E-Smith on 16 megs ... then if you have 130 megs free then one could say that you have too much.

Another reason that it may "appear" Linux is using a large amount of RAM is that in addition to buffering (aka caching) files on the disk, Linux also buffers the swap area (aka virtual memory).  So that if a program requires information that is held in the swap area the kernel may be able to retrieve this information from disk buffer rather than waiting for the information to be read off the disk.  Then if the system needs more RAM eg to run a program, then the kernel is able to discard this disk buffer as the information is already written on disk "as virtual memory".

I hope this helps.

Caio

Carl