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CPU cache miss stats

Hi,

Is there any way to collect CPU cache misses statistics?

Does the Intel CPU at all collect this info?

I have just been to a client where a 1.8GHz P-4 machine with 512KB cache 
took ~11 minutes to compile a certain file, while a 550MHz P-III with 
256KB cache took ~10 *hours*. Virtual memory was never used in either of 
the cases. Top showed g++ taking (almost) all the CPU in user mode. 
Compiling without optimizations was quick on both machines.

I eventually solved this particular problem by changing the sources in a 
way that I deemed would make the g++ optimizer require less memory. The 
change indeed worked (2.5min on the fast machine, 5min on the slow 
machine). I am still wondering, though, whether a CPU cache miss was 
indeed the problem, and I was wondering whether there is any way of 
getting an authorative answer (as well as debugging this without using 
hunches and guesswork).

             Many thanks,

                      Shachar

-- 
Shachar Shemesh
Open Source integration consultant
Home page & resume - http://www.shemesh.biz/


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