Will,

On Thu, May 17, 2007 at 09:27:16AM -0400, William Cohen wrote:
> 
> A graduate student at NCSU, Jesse Beu, has used the PEBS registers to do 
> this type of sampling on P4 based processors running a perfmon2 kernel. His 
> master's thesis describes how this was accomplished. The main problem is 
> the PEBS hardware doesn't directly give address information; it give 
> processor state information. Computing the address from the state 
> information is possible, but non-trivial.
> 
> I don't think that AMD Opterons have hardware that allows that. The AMD 
> Family 10 processors are suppose to have some type of sampling mechanism to 
> allow collection of memory reference addresses.
> 
> 
> Another possible suggestion is to make use of the TLB hardware and mark 
> pages as unreadable and then have the trap hander do some data collection.
> 
Yes, I agree with this technique. But you probably need some kernel support
to make this fast.

-- 
-Stephane
_______________________________________________
perfmon mailing list
[email protected]
http://www.hpl.hp.com/hosted/linux/mail-archives/perfmon/

Reply via email to