28 lines
790 B
ReStructuredText
28 lines
790 B
ReStructuredText
.. _pgo:
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===========================
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Profile Guided Optimization
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===========================
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:abbr:`PGO (Profile Guided Optimization)` is the process of adding
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probes to a compiled binary, running said binary, then using the
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run-time information to *recompile* the binary to (hopefully) make it
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faster.
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How PGO Builds Work
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===================
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The supported interface for invoking a PGO build is to add ``MOZ_PGO=1`` to
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configure flags and then build. e.g. in your mozconfig::
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ac_add_options MOZ_PGO=1
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Then::
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$ ./mach build
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This is roughly equivalent to::
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#. Perform a build with *--enable-profile-generate* in $topobjdir/instrumented
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#. Perform a run of the instrumented binaries with build/pgo/profileserver.py
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#. Perform a build with *--enable-profile-use* in $topobjdir
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