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From: Anton Yuzhaninov <citrin@citrin.ru>
Date: Tue, 20 Sep 2011 16:12:57 +0000 (UTC)
Organization: Vega
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Subject: hwpmc overflow
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It seems to be, that hwpmc counters overflow is not properly handled.

I want to count TLB misses and run:

pmcstat -C -w1 -d -p
INSTR_RETIRED_ANY -p DTLB_MISSES.ANY -p MEM_LOAD_RETIRED.DTLB_MISS -p
ITLB_MISSES.ANY -p MEM_LOAD_RETIRED.L3_MISS

With -C values should monotonous increase, but in output I see
overflous.

Example output:
http://pastebin.com/JiEF9AcU

2120463169
2139646836
281472837488169
281472855479093

2139646836 is near to 2^31 - max value for signed int (int32_t)

-- 
 Anton Yuzhaninov