topic Re: difference between glance and top in Operating System - HP-UX

difference between glance and top

223848 — Tue, 11 Jan 2011 11:43:16 GMT

Hi Gurus,
I have a small doubt.
In one of the 11iv2 server when i checked with top command one of the process is taking 99% of CPU.
But when i checked in glance with that particular process PID it is taking very small CPU utilisation only..

Can you please tell me why is it so and from where these (top and glance) are getting the statistics.

Any way i restarted that particular apllication And after that this process is not shown in the top output.

Re: difference between glance and top

sarfaraj ahmad — Tue, 11 Jan 2011 11:51:42 GMT

Hi laiju,

Glance is more reliable than top and gives appropriate result and statistics.

Re: difference between glance and top

Manix — Tue, 11 Jan 2011 11:56:36 GMT

Hello Laiju !!

How how are you checking the output in Glance

run Glance

type "s" to enter PID
& checking "CPU Usage util" for that process.

There is some refresh count for Glance.

Please paste the output.

Thanks

Manix

Re: difference between glance and top

223848 — Tue, 11 Jan 2011 12:19:42 GMT

Hi Manix,
As i already mentioned you the problem is solved by restarting the application, so i am unable to give you the output now.

What i did is , i gave glance command, then i checked the process states the i pressed R and give the ID of that particular process. At that time i can see only 0.1% only that partical process is using.

But at the same time i checked the usage of that process in top, at that time that process was the top CPU usage in the system.

Re: difference between glance and top

Manix — Tue, 11 Jan 2011 12:25:44 GMT

Got u !!

difficult to state as node is not in same state.
but yes Glance is more powerful & reliable then
top.

Thanks
Manix

Re: difference between glance and top

223848 — Tue, 11 Jan 2011 12:29:26 GMT

can you please tell me from where this top and glance are getting the outputs.

Re: difference between glance and top

Sreer — Tue, 11 Jan 2011 12:37:01 GMT

Hi,
Glance will give more statistical o/p and is more reliable than top.

Better to get the o/p of galnce/top to tell more.

Rgds
Sree

Re: difference between glance and top

Manix — Tue, 11 Jan 2011 12:38:43 GMT

the difference depends on the time at which both took the samples. top gets it's data from kernel counters whereas a glance pulls it from it's own measurement instrumentation.

When glance took the sample, process may be sleeping and when top took it, it might be running. So, looking at cumulative CPUs of both the tools over a certain period may make some sense but I wouldn't go too far in trying to compare piece to piece.

'top' may report wrong results depending on the patch levels though on 11i it seems to be fairly good. I use top just to have a quick look at the system. But I would always rely on glance as it gives a lot more information than top.

Look at the patch levels as well !!

Patch Name: PHKL_29198
Patch Description: s700_800 11.11 Psets Enablement Patch; top(1)

Re: difference between glance and top

Ismail Azad — Tue, 11 Jan 2011 12:44:08 GMT

Hi,

Top is a generic unix tool and glance is HP proprietary and hence on an HPUX operating system, glance is much more reliable than top or sar. Top is typically related to fetching of info from (/dev/kmem),(/dev/mem) so do the generic unix tools sar, vmstat and iostat. Glance and gpm are proprietary to HPUX and should be preferred over top or sar although they are still very useful.

Regards
Ismail Azad

Re: difference between glance and top

Alzhy — Tue, 11 Jan 2011 18:51:44 GMT

Correction:

Glance versions exist for practically most UNIX and Linux variants.

For large corporates, it is often that Glance is deployed as a standard tool.

Difference: Glance has simply more bells and whistles and can collect historical data, set up alarms, group applications, etc.

If you've deep pockets -- Glance (and other OpenView Products) is a good choice.

BUT - if you have in house expertise or Open Source Software IS acceptable, there are solutions that cost NIL. Take the case of NAGIOS -- which HP has been incorporating and offering in some of its suites.

It may actually be on the Internet Express Suite of OSS tools and utilities already.

Re: difference between glance and top

Alzhy — Tue, 11 Jan 2011 18:52:59 GMT

Yep -- NAGIOS is now offered in IExpress:

https://h20392.www2.hp.com/portal/swdepot/displayProductInfo.do?productNumber=HPUXIEXP1131

Re: difference between glance and top

Ismail Azad — Wed, 12 Jan 2011 04:49:43 GMT

Hi,

> Alzhy

What i meant was glance is a performance monitoring tool that was developed by HP and was used initially on HPUX. :).

Regards
Ismail Azad