Performance issue

[kunjuttan]

What to do if the connected users are saying server performance is very slow ?

[R.K. # · Accepted solution]

HI Dipesh,

Try finding which part of server have issues.

Memory consumption
CPU usage
Disk bottleneck
Network issues
etc..

[kunjuttan]

Thanks,but how to find..??

[R.K. #]

More details reuired from your side:

-OS version
-model
-applicaiton running
-when did issue start
-any changes sw/hw made to server
-any other you think that can be relevant

-Please ask the users where when how they face performace issues.
-Is it specific to any file system?
-swapinfo -tam <-- to check swap usage
-top <-- to check cpu usage

[kunjuttan]

Thank you Mr.RK.
But the thing is that I just want to know what all thigs is to be checked and how to, if connected users are saying server performance is very slow.

[Jeeshan]

You can also check the buffer and inode usage

#sar -v 5 5

#sar -b 5 5

[kunjuttan]

Can anybody give me some more details.

[R.K. #]

Hi Again,

During peak usage (when users say system is slow), check swap usage (percent used):

#swapinfo -tam
The key areas to monitor are reserve, memory and total.

# dmesg
Collect system diagnostic messages to form error log.

# more /var/adm/syslog/syslog.log
Check for any Error or Warning messages

# sar -b 5 10
To check buffer cache. Typically %wcache should 95 or greater most of the time.

# sar -Mu 5 10
To check cpu load
%wio - should be less close to 0 (depends on working environment)
%idle - should be high more than 80 (depends on working environment)

[amithp]

IF you have glance or GPM installed
run /opt/perf/bin/glance.

the first four rows will show you the critical metrics utilisation
viz(CPU,DISK,MEMORY,SWAP OR NETWORK).

This will give you fair idea why system is slow.

Below that it will show you the various process and resource utilistion done by them.
You can sort them as per the particular resource utilisation.

Glance have various options to drill down into the problem.

If all resources seems to be OK check with
the system load

$uptime
will show the load on the system. usually load below 1 is ok if it is 1 or more ask your users to check their applications.

[kunjuttan]

"# sar -b 5 10
# sar -Mu 5 10"

Here what is this 5 and 10 means?