Muhammad,

I do have a patch allowing the Oprofile kernel module to multiplex 
between different events. The patch is still under development and 
testing, and it might not be 100% stable at this time.

I was not planning to send it out until fully tested, but if you find it 
useful and have any fix, question, or comment please let me know.

You also need to make a few oprofile changes:

1. Modify the nr_counters for the CPU you are running in op_cpu_type.c
2. Modify the allowed counter in the events file in events/x86-64/<cpu 
type>/events.

Jason

Muhammad Atif wrote:
> Dear users/developers
> Forgive me for asking a basic question. Is there a way to efficiently multiplex hardware events in oprofile? I have AMD opterons and I want to profile certain MPI applications for various hardware events. Now my system only supports 4 events, and to get more counters in one run, I have to do tedious work of stop, kill, set events, start the oprofiled with opcontrol. This is time consuming job and we end up loosing useful information. 
> As we need to do some anlysis on Xen guests, therefore we cannot make use of PAPI etc, which support multiplexed event measurement.  
> 
> 
> Best Regards,
> Muhammad Atif
>