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pmc: pmc frontend stall analysis based on IBS
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Authored by ali_mashtizadeh.com on Jun 23 2026, 4:27 PM.
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Details

Summary

The frontend command uses AMD IBS frontend events to analyze the major
sources of frontend stalls. It displays a table breakind down the major
causes of front end stalls. This is a simple demonstration of the tools
as you can use the filtering tools to limit the analysis to a subset of
the samples including filtering by fetch latencies.

Sponsored by: Netflix

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rG FreeBSD src repository
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ali_mashtizadeh.com created this revision.
adrian added a subscriber: adrian.
adrian added inline comments.
usr.sbin/pmc/cmd_pmc_frontend.cc
138

Do you think it's worth adding cycles spent walking page tables?

This revision is now accepted and ready to land.Jun 30 2026, 5:49 PM
This revision was automatically updated to reflect the committed changes.