Active IQ Unified Manager Discussions

Monitoring CPU impact of compression and de-compression


Currently we are suffering from high CPU on compression en de-compression on our CIFS only filer. A sent perfstat.out to Netapp states that the CPU is working hard to decompress files while accesing them.

Is there a way to monitor compression en de-compression action with specific counters in DFM, or command line?

And what are the counters to look at? When do we reach a bottleneck, so we need to turn it off.

Users experience slow CIFS access on this filer. Sometimes it is slow, some time it is fast. There is not really a pinpoint on exact time.




Tomas -

This is one of the most interesting questions I've seen recently !

The short answer -

As far as I can tell compression and decompression is part of the kahuna domain - it isn't CIFs specific.

You might want to try and look for a correlation between CPU(or kahuna) and cifs read activity in OnComand Unified Manager (DFM).

I don't advise customers to turn on compression in high read activity environs, we do caution that it can be a CPU hit on decompression.

I'm going to try and run some tests on my lab environ here, and see if I can tell you any more...

I hope this response has been helpful to you.

At your service,

Eugene E. Kashpureff

Senior Netapp Instructor, Unitek Education

(P.S. I appreciate points for helpful or correct answers.)

Me thinks I'm in love with my job !