tools/perf/Documentation/perf-diff.txt

Source file repositories/reference/linux-study-clean/tools/perf/Documentation/perf-diff.txt

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Linux kernel
Corpus path
tools/perf/Documentation/perf-diff.txt
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.txt
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309
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: documentation
Status
atlas-only

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Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

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perf-diff(1)
============

NAME
----
perf-diff - Read perf.data files and display the differential profile

SYNOPSIS
--------
[verse]
'perf diff' [baseline file] [data file1] [[data file2] ... ]

DESCRIPTION
-----------
This command displays the performance difference amongst two or more perf.data
files captured via perf record.

If no parameters are passed it will assume perf.data.old and perf.data.

The differential profile is displayed only for events matching both
specified perf.data files.

If no parameters are passed the samples will be sorted by dso and symbol.
As the perf.data files could come from different binaries, the symbols addresses
could vary. So perf diff is based on the comparison of the files and
symbols name.

OPTIONS
-------
-D::
--dump-raw-trace::
        Dump raw trace in ASCII.

--kallsyms=<file>::
        kallsyms pathname

-m::
--modules::
        Load module symbols. WARNING: use only with -k and LIVE kernel

-d::
--dsos=::
	Only consider symbols in these dsos. CSV that understands
	file://filename entries.  This option will affect the percentage
	of the Baseline/Delta column.  See --percentage for more info.

-C::
--comms=::
	Only consider symbols in these comms. CSV that understands
	file://filename entries.  This option will affect the percentage
	of the Baseline/Delta column.  See --percentage for more info.

-S::
--symbols=::
	Only consider these symbols. CSV that understands
	file://filename entries.  This option will affect the percentage
	of the Baseline/Delta column.  See --percentage for more info.

-s::
--sort=::
	Sort by key(s): pid, comm, dso, symbol, cpu, parent, srcline.
	Please see description of --sort in the perf-report man page.

-t::
--field-separator=::

	Use a special separator character and don't pad with spaces, replacing
	all occurrences of this separator in symbol names (and other output)
	with a '.' character, that thus it's the only non valid separator.

Annotation

Implementation Notes