Messages in this thread | | | Date | Tue, 5 Jul 2011 18:01:36 +0200 | Subject | Re: [PATCH 1/4] perf, x86: Add Intel Nehalem/Westmere uncore pmu | From | "Andi Kleen" <> |
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> >> But it's not strictly required I would say, >> 44(?) bits are probably enough for near all use cases. > > 44bits is in the hours range for pure cycle counts, which is so-so. I > bet you're going to be very annoyed when you find your counters are > wrecked after your 5 hour test run finishes.
For these kinds of long running measurements you usually care about ratios, not absolutes. Some infrequent wrapping should not substantially change. those.
-Andi
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