Re: [PATCH 4/5] perf record: mmap output file - v5

From: David Ahern
Date: Mon Nov 18 2013 - 21:17:51 EST


On 11/18/13, 7:13 PM, Namhyung Kim wrote:
I think it should be

perf record -e cycles -F 4000 -e faults -c 1 --call-graph dwarf,8192 -a -- sleep 1

(at least to generate the feedback spiral more efficiently..)

you don't need the cycles. faults by itself works. Each event contains > 2 pages of data in the sample. With mmap-based output a single sample (1 page fault in any process) generates 2-3 page faults by perf which cause 2-3 >8k samples to be generated, which generates faults, ....

David


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