Messages in this thread | | | From | Lucas De Marchi <> | Date | Fri, 13 Nov 2009 12:46:26 -0200 | Subject | Re: perf stat output |
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On Fri, Nov 13, 2009 at 06:07, Peter Zijlstra <peterz@infradead.org> wrote: > On Thu, 2009-11-12 at 20:03 -0200, Lucas De Marchi wrote: >> Hi all! >> >> Some questions about perf stat output. See example: >> >> >> lucas@LMS-linux:~/programming/testprograms> perf stat -e >> L1-dcache-loads -e L1-dcache-load-misses -- make -j >> gcc test_schedchanges.c -o test_schedchanges >> gcc -pthread test_taskaff1.c -o test_taskaff1 >> gcc -pthread test_taskaff2.c -o test_taskaff2 >> gcc -pthread test_taskaff3.c -o test_taskaff3 >> >> Performance counter stats for 'make -j': >> >> 161384667 L1-dcache-loads # 0.000 M/sec >> 24853791 L1-dcache-load-misses # 0.000 M/sec >> >> 0.066893389 seconds time elapsed >> >> Why do we have both L1-dcache-loads and L1-dcache-load-misses with >> 0.000 M/sec? Also, why do we have 0 M/s when running "perf stat -a -e >> cache-misses -e cache-references" but values different than 0 when >> running "perf stat -a" without selecting the events? > > No idea, you'd have to look at the code computing this M/sec stuff. I > think Ingo wrote that, so he might have an idea.
But should it be, for example, L1-dcache-loads / seconds time elapsed, or does it have another meaning?
Lucas De Marchi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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