hwpmc: Permit the minimum sampling count to be set as a sysctl.
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Authored by jhb on Jun 3 2022, 10:02 PM.

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mav
mhorne
gnn

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manpages

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rG46b46bb77405: hwpmc: Permit the minimum sampling count to be set as a sysctl.
rGca341f3cf52f: hwpmc: Permit the minimum sampling count to be set as a sysctl.

Summary

A rarely occurring event (e.g. an event that occurs less than 1000
times during execution of a program) may require a lower minimum
threshold than 1000. Replace the hardcoded 1000 with a sysctl that
the administrator can use to permit smaller sampling count values.

Sponsored by: University of Cambridge, Google, Inc.

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rG FreeBSD src repository

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Event Timeline

jhb created this revision.Jun 3 2022, 10:02 PM

Herald added a subscriber: imp. · View Herald TranscriptJun 3 2022, 10:02 PM

jhb requested review of this revision.Jun 3 2022, 10:02 PM

Harbormaster completed remote builds in B45844: Diff 106623.Jun 3 2022, 10:03 PM

I agree that the hard coded limitation is annoying. I hurt me also when I've tried to profile something with PCM_SOFT and low event rate. It is good to have it at least configurable.

This revision is now accepted and ready to land.Jun 4 2022, 12:49 AM

Please add this to the sysctl section in hwpmc(4).