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[ThinLTO] Default backend threads to heavyweight_hardware_concurrency
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Authored by tejohnson on Oct 19 2016, 8:53 AM.

Details

Summary

Changes default backend parallelism from thread::hardware_concurrency to
the new llvm::heavyweight_hardware_concurrency, which for X86 Linux
defaults to the number of physical cores (and will fall back to
thread::hardware_concurrency otherwise). This avoid oversubscribing
the physical cores using hyperthreading.

Diff Detail

Repository
rL LLVM

Event Timeline

tejohnson updated this revision to Diff 75160.Oct 19 2016, 8:53 AM
tejohnson retitled this revision from to [ThinLTO] Default backend threads to heavyweight_hardware_concurrency.
tejohnson updated this object.
tejohnson added reviewers: mehdi_amini, pcc.
tejohnson added a subscriber: llvm-commits.
mehdi_amini accepted this revision.Oct 19 2016, 9:10 AM
mehdi_amini edited edge metadata.

LGTM.

This revision is now accepted and ready to land.Oct 19 2016, 9:10 AM
This revision was automatically updated to reflect the committed changes.