Hi Will,

Good show on the list of tests. When I spent a week with Stefane about a
month back, we rooted out 4 or 5 bugs ust from getting a full port of
PAPI running. 

In regards to FP_OPS, I'm afraid to say that these are very poorly
classified on x86 type processors (except the recent architected PMU
models)...This also goes for x86_64 variants...depending on whether one
uses SSE or x87, packed or unpacked, single or double, changes the
counts greatly. On AMD64, there's no exact way to measure fpops, as
various combinations of mov are also counted in the FP pipe. 

We've had this problem for years in PAPI, my recommendation is to make a
small code module for each processor that designates a particular PFM
event and a piece of inlined code that can generate that event. 

Hope this saves you the years of headaches it's given us.

Phil

On Fri, 2006-10-27 at 17:26 -0400, William Cohen wrote:
> One of the complications I noticed is that each processor's
> performance 
> monitoring hardware has it own set of events available. For some of
> the existing 
> ia64 specific tests unaligned access are used. I assume that this was
> selected 
> because it was a rare event and the number of events could be counted
> precisely 
> on the ia64. However, this isn't going to translate to other
> processors. Would 
> floating point be a reasonable substitution for that? Floating point
> operations 
> would be rare on integer code and in the kernel. 

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