Re: [PerfSuite-users] monitoring the same process 2

[Rick K. <rk...@nc...>]

Giuseppe,

> I am using perfsuite with PAPI, but I am not sure if multiplexing is 
> enabled. How to verify it? Is it necessary to install MPX?
> Variation that occurs are up to  100 % so unuseful for me, and I always 
> use the same intel compiler with the same option. Thanks, Giuseppe.
> 

It's not necessary to install MPX.  That's a software layer that was 
developed by John May at Lawrence Livermore.  It's the basis for PAPI's 
multiplexing and so comes with PAPI.  It's used when you are using 
PerfSuite in counting (not profiling) mode, and you can tell when it has 
been enabled by either looking in the "Statistics" section of psprocess 
output or looking at the XML output files that psrun creates.

If you have a program that runs for a very short time, it's possible that 
you may see many event counts of zero, and typically that occurs because 
the process is so short-lived, there is not enough time to cycle through 
all the events.  You can force runs to happen without multiplexing by 
creating your own configuration file; there is a short description of how 
to do so here:

http://perfsuite.ncsa.uiuc.edu/libpshwpc/sampleconfig.html

Rick