topic Re: Memory utilization in Operating System - Linux

Memory utilization

Shahul — Sun, 02 May 2004 13:41:14 GMT

Hi,

Any one knows how to monitor memory usage in Linux servers. I am very new to Linux systems. is there any tool as such or any command which can monitor and give a report of memory usage. May be like Glance plus in HP.

TIA
Shahul

Re: Memory utilization

Vernon Brown_4 — Sun, 02 May 2004 15:55:44 GMT

From a terminal you can issue the command:

top

from the command line. It shows a summery of resource usage as well as processes. Also

man top

will give you some documentation on the top process.

There is a system monitor in the GUI under system I think.

Vern

Re: Memory utilization

Rodney McKee_1 — Sun, 02 May 2004 17:38:47 GMT

Shahul

sar - part of sysstat package. "sar -rR" this is also easy to run through gplot to get a graphic output.
top - check some of the switches to have it report on memory etc as required.
gnome-system-monitor - This comes with Red Hat and can provide a realtime view of top and some graphs

Glance is available for Linux, looks to have some issues with motifversions but does look to work.
Hope this helps

Re: Memory utilization

Martin P.J. Zinser — Sun, 02 May 2004 18:02:08 GMT

Hello,

/proc/meminfo contains dynamically updated information on the overall memory status of the system.

Greetings, Martin

Re: Memory utilization

Steven E. Protter — Sun, 02 May 2004 19:40:41 GMT

Here are a couple of sar scripts that you can adapt to do meeasurement over time to a file in Linux. You'll need to comment out the HP-UX stuff which is obvious.

See attachment.

SEP

Re: Memory utilization

Roberto Polli — Mon, 03 May 2004 04:44:47 GMT

try vmstat.

#man vstat

Peace, R.

Re: Memory utilization

Alexander Chuzhoy — Mon, 03 May 2004 05:33:55 GMT

and of course the
free
utility.
man free - for more information

Re: Memory utilization

Shahul — Mon, 03 May 2004 12:32:11 GMT

Hi,

Thanks to your reply. Yes, I have analyzed with top, sar and free, and also by ps commend. I could see my system's 96% memory is utilized in top command. But PS commend shows only 370MB is used by processes. I have 1.25GB of memory installed. Could someone explain me how the remaining memory is utilized.

TIA
Shahul

Re: Memory utilization

Don_89 — Mon, 03 May 2004 14:11:58 GMT

Linux uses all available memory becuase , all together now, unused memory is wasted memory.. I always do a free -m from the command line which displays the info in megabytes. The first line will have the following catagoies..

Total: Total system memeory
Used: Disk cache, Page Swap, running processes
Shared: Memory used that is shared between process
buffers: Memory pages swaped out to memory not disk
cached: disk cache

The next line is the actual memory used by processes/programs and memory free

used: progams/process
free: memory avaiable for programs/processes

The last line is for virutal memory which hopefully you'll never use.

Checkout this link for linux memory usage. It gets pretty technical though..

http://home.earthlink.net/~jknapka/linux-mm/vmoutline.html

Re: Memory utilization

Francisco J. Soler — Mon, 03 May 2004 15:27:39 GMT

Hi,

KDE and Gnome have some nice graphical interfaces to monitor the system resources, memory, disk etc.

If you have installed it in your server you can try:

gnome-system-monitor and ksysguard

i think it is not very useful in a server but it could help you to monitor the system status.

Frank.

Re: Memory utilization

Steven E. Protter — Mon, 03 May 2004 18:29:13 GMT

I you have X installed you can run gtop to run the gnome graphical top utility.

HP might have ported glance to Linux but that costs bucks.

SEP

Re: Memory utilization

Guru Dutta — Tue, 04 May 2004 04:41:39 GMT

Hi,

I guess with addition to top,sar,vmstat u can use gmond iff u have a cluster setup.