kernel/tools/perf/Documentation/perf-diff.txt, branch linux-3.11.y

perf diff: Remove displacement output option

2012-12-09T11:46:07Z

It seems not very useful, because it's possible and event more convenient to lookup related symbol by name. Also the output value for both 'baseline' and 'new' data is quite apparent from diff output. And above all it complicates hist code factoring ;) Ditching out PERF_HPP__DISPL column with related output functions. Suggested-by: Arnaldo Carvalho de Melo Signed-off-by: Jiri Olsa Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Ingo Molnar Cc: Namhyung Kim Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/20121206132228.GB1080@krava.brq.redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add -F option to display formula for computation

2012-10-05T17:13:36Z

Adding -F option to display the formula for specified computation. This is mainly to facilitate debugging, but can be useful anyway. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-7-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add -p option to display period values for hist entries

2012-10-05T17:11:47Z

Adding -p option to show period values for both compared hist entries. Showing hist column PERF_HPP__PERIOD and newly added hist column PERF_HPP__PERIOD_BASELINE. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-6-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add weighted diff computation way to compare hist entries

2012-10-05T17:10:42Z

Adding 'wdiff' as new computation way to compare hist entries. If specified the 'Weighted diff' column is displayed with value 'd' computed as: d = B->period * WEIGHT-A - A->period * WEIGHT-B - A/B being matching hist entry from first/second file specified (or perf.data/perf.data.old) respectively. - period being the hist entry period value - WEIGHT-A/WEIGHT-B being user suplied weights in the the '-c' option behind ':' separator like '-c wdiff:1,2'. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-5-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add option to sort entries based on diff computation

2012-10-05T17:08:54Z

Adding support to sort hist entries based on the outcome of selected computation. It's now possible to specify '+' as a first character of '-c' option value to make such sort. Example: $ perf diff -c ratio -b # Event 'cache-misses' # # Baseline Ratio Shared Object Symbol # ........ .............. ................. ................................ # 19.64% 0.69 [kernel.kallsyms] [k] clear_page 0.30% 0.17 [kernel.kallsyms] [k] mm_alloc 0.04% 0.20 [kernel.kallsyms] [k] kmem_cache_alloc $ perf diff -c +ratio -b # Event 'cache-misses' # # Baseline Ratio Shared Object Symbol # ........ .............. ................. ................................ # 19.64% 0.69 [kernel.kallsyms] [k] clear_page 0.04% 0.20 [kernel.kallsyms] [k] kmem_cache_alloc 0.30% 0.17 [kernel.kallsyms] [k] mm_alloc Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-4-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add ratio computation way to compare hist entries

2012-10-05T17:06:54Z

Adding -c option to select computation method with the current 'Delta' computation as default. Current possible values are of this option are: 'delta' and 'ratio'. Adding 'ratio' as new computation way to compare hist entries. If specified the 'Ratio' column is displayed with value 'r' computed as: r = A->period / B->period with: - A/B being matching hist entry from first/second file specified (or perf.data/perf.data.old) respectively. - period being the hist entry period value Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-3-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Add -b option for perf diff to display paired entries only

2012-10-05T17:05:14Z

Adding -b option to perf diff command to display only entries with match in the baseline. Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1349448287-18919-2-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Make diff command work with evsel hists

2012-09-08T00:44:02Z

Putting 'perf diff' command back on track with the 'latest' evsel hists changes. Each evsel has its own 'hists' object gathering stats for the particular event. While currently counts are accumulated for the whole session regardless of the events diversification within compared sessions. The 'perf diff' command now outputs all matching events within compared sessions (with event name specified). The per event diff output stays the same. $ ./perf diff # Event 'cycles' # # Baseline Delta Shared Object Symbol # ........ .......... ................. .............................. # 0.00% +15.14% [kernel.kallsyms] [k] __wake_up 0.00% +13.38% [kernel.kallsyms] [k] ext4fs_dirhash ... SNIP 0.00% +0.42% [kernel.kallsyms] [k] local_clock 0.17% -0.05% [kernel.kallsyms] [k] native_write_msr_safe # Event 'faults' # # Baseline Delta Shared Object Symbol # ........ .......... ................. .............................. # 0.00% +79.12% ld-2.15.so [.] _dl_relocate_object 0.00% +11.62% ld-2.15.so [.] openaux Signed-off-by: Jiri Olsa Cc: Andi Kleen Cc: Corey Ashford Cc: David Ahern Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul E. McKenney Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1346946426-13496-2-git-send-email-jolsa@redhat.com Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Add symfs option for off-box analysis using specified tree

2010-12-21T22:17:51Z

The symfs argument allows analysis of perf.data file using a locally accessible filesystem tree with debug symbols - e.g., tree created during image builds, sshfs mount, loop mounted KVM disk images, USB keys, initrds, etc. Anything with an OS tree can be analyzed from anywhere without the need to populate a local data store with build-ids. Commiter notes: o Fixed up symfs="/" variants handling. o prefixed DSO__ORIG_GUEST_KMODULE case with symfs too, avoiding use of files outside the symfs directory. LKML-Reference: <1291926427-28846-1-git-send-email-daahern@cisco.com> Signed-off-by: David Ahern Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Document missing options

2010-12-01T20:22:46Z

Cc: Ingo Molnar Cc: Paul Mackerras Cc: Peter Zijlstra LKML-Reference: <1291168642-11402-5-git-send-email-shawn.bohrer@gmail.com> Signed-off-by: Shawn Bohrer Signed-off-by: Arnaldo Carvalho de Melo