Would I use TA-nmon to get nmon performance data to Splunk, but still have another nmon process to write .nmon file?

[leo_wang]

Hi,
I am happy to hear that after TA-nmon v1.3 , they use the new process ( named pipe ) to reduce cpu usage of TA-nmon.
( In my previous test , the old TA-nmon will consume about 20% CPU usage when processing *.nmon files... it's horrible !! )

But for some reason , I need to keep *.nmon files for our servers.
So if I have an nmon process keep running by cron job in my server ( To generate .nmon file).

The "nmon_helper.sh" ( The nmon trigger in TA-nmon ) will ignore it ? or kill it ?

I have read the following document, but still not quite sure about what it will act :
http://ta-nmon.readthedocs.io/en/latest/data_processing.html

[guilmxm · Accepted solution]

Hi !

Sorry for late reply, I always try to reply shortly but it seems I missed the notification.

I appreciate the foot print of the old TA-nmon was potentially problematic (while it was normally far from 20%), this problem is now solved and the 1.3.x branch provides a very low and stable foot print. (If you read the doc and it seems you did, you've probably seen the benchmark section)

To answer your question, I understand you need and want to keep having an nmon file collection, this makes sense and can be useful as they can easily be transferred, analysed else where, etc.

Hopefully, the TA-nmon will not have any issue if you an other nmon process running, this is totally independent and will not interfere with the TA-nmon behaviours.

Finally, having 2 nmon processes (one that you manage and writes to your file collection, and the other from the TA-nmon) is not a problem at all, the nmon binary footprint is very low, not a problem at all.

The nmon_helper.sh script does not kill any process, it restricts processes searches to the Splunk context and will accommodate with other nmon processes.

I hope this answers your question.

Guilhem

Notes: I will update the TA-nmon on-line doc to mention this.

[leo_wang]

Hi,
Thanks for your response...
And I still have another question :

Is it possible to let "TA-mon" keep the .nmon file ( And rotate it once a day ) ?
So I could disable our nmon job on crontab , and keep only one nmon process in our server.
( To mininze to CPU usage... )

[guilmxm]

Hi,

You are welcome.

You cannot strictly use the existing stuff in the TA-nmon to generate nmon flat files, specially because it uses named pipe files since the 1.3.x. (and the previous version was using short life cycle of nmon file)

But you can definitely include a simple script on your own in the TA-nmon that will be scheduled and will start an nmon process once per day, nothing complex at all.
And if you do so, yes you can remove your crontab entry.

Guilhem

[guilmxm]

Note you MUST not try to create a long cycle life time nmon file that will be consistently read by the TA-nmon or you will very quickly face very large CPU usage.

The TA-nmon uses its own stuff (fifo files), you can tweak this with supported options but you must not replace it.

Finally, an nmon process has a very low CPU usage, having 2 processes running in the same time is no big deal. (not more than 2 users running top in the same time)