litmus-rt-budgetable-locks.git/.git/tools/perf/Documentation/perf-report.txt, branch update_litmus_2019

perf report: Add --switch-on/--switch-off events

2019-08-16T15:14:33+00:00

Since 'perf top' shares the histogram browser with 'perf report', then
the same explanation in the previous cset applies.

An additional example uses a pair of SDT events available for systemtap:

  # perf probe --exec=/usr/bin/stap '%*:*'
  Added new events:
    sdt_stap:benchmark__thread__start (on %* in /usr/bin/stap)
    sdt_stap:benchmark   (on %* in /usr/bin/stap)
    sdt_stap:benchmark__thread__end (on %* in /usr/bin/stap)
    sdt_stap:pass6__start (on %* in /usr/bin/stap)
    sdt_stap:pass6__end  (on %* in /usr/bin/stap)
    sdt_stap:pass5__start (on %* in /usr/bin/stap)
    sdt_stap:pass5__end  (on %* in /usr/bin/stap)
    sdt_stap:pass0__start (on %* in /usr/bin/stap)
    sdt_stap:pass0__end  (on %* in /usr/bin/stap)
    sdt_stap:pass1a__start (on %* in /usr/bin/stap)
    sdt_stap:pass1b__start (on %* in /usr/bin/stap)
    sdt_stap:pass1__end  (on %* in /usr/bin/stap)
    sdt_stap:pass2__start (on %* in /usr/bin/stap)
    sdt_stap:pass2__end  (on %* in /usr/bin/stap)
    sdt_stap:pass3__start (on %* in /usr/bin/stap)
    sdt_stap:pass3__end  (on %* in /usr/bin/stap)
    sdt_stap:pass4__start (on %* in /usr/bin/stap)
    sdt_stap:pass4__end  (on %* in /usr/bin/stap)
    sdt_stap:benchmark__start (on %* in /usr/bin/stap)
    sdt_stap:benchmark__end (on %* in /usr/bin/stap)
    sdt_stap:cache__get  (on %* in /usr/bin/stap)
    sdt_stap:cache__clean (on %* in /usr/bin/stap)
    sdt_stap:cache__add__module (on %* in /usr/bin/stap)
    sdt_stap:cache__add__source (on %* in /usr/bin/stap)
    sdt_stap:stap_system__complete (on %* in /usr/bin/stap)
    sdt_stap:stap_system__start (on %* in /usr/bin/stap)
    sdt_stap:stap_system__spawn (on %* in /usr/bin/stap)
    sdt_stap:stap_system__fork (on %* in /usr/bin/stap)
    sdt_stap:intern_string (on %* in /usr/bin/stap)
    sdt_stap:client__start (on %* in /usr/bin/stap)
    sdt_stap:client__end (on %* in /usr/bin/stap)

  You can now use it in all perf tools, such as:

  	perf record -e sdt_stap:client__end -aR sleep 1

  #

From these we're use the two below to run systemtap's test suite:

  # perf record -e sdt_stap:pass2__*,cycles:P make installcheck > /dev/null
  ^C[ perf record: Woken up 8 times to write data ]
  [ perf record: Captured and wrote 2.691 MB perf.data (39638 samples) ]
  Terminated
  # perf script | grep sdt_stap
              stap 28979 [000] 19424.302660: sdt_stap:pass2__start: (561b9a537de3) arg1=140730364262544
              stap 28979 [000] 19424.333083:   sdt_stap:pass2__end: (561b9a53a9e1) arg1=140730364262544
              stap 29045 [006] 19424.933460: sdt_stap:pass2__start: (563edddcede3) arg1=140722674883152
              stap 29045 [006] 19424.963794:   sdt_stap:pass2__end: (563edddd19e1) arg1=140722674883152
  # perf script | grep cycles |  wc -l
  39634
  #

Looking at the whole perf.data file:

  [root@quaco testsuite]# perf report | grep cycles:P -A25
  # Samples: 39K of event 'cycles:P'
  # Event count (approx.): 34044267368
  #
  # Overhead  Command  Shared Object         Symbol
  # ........  .......  ....................  ................................
  #
       3.50%  cc1      cc1                   [.] ht_lookup_with_hash
       3.04%  cc1      cc1                   [.] _cpp_lex_token
       2.11%  cc1      cc1                   [.] ggc_internal_alloc
       1.83%  cc1      cc1                   [.] cpp_get_token_with_location
       1.68%  cc1      libc-2.29.so          [.] _int_malloc
       1.41%  cc1      cc1                   [.] linemap_position_for_column
       1.25%  cc1      cc1                   [.] ggc_internal_cleared_alloc
       1.20%  cc1      cc1                   [.] c_lex_with_flags
       1.18%  cc1      cc1                   [.] get_combined_adhoc_loc
       1.05%  cc1      libc-2.29.so          [.] malloc
       1.01%  cc1      libc-2.29.so          [.] _int_free
       0.96%  stap     stap                  [.] std::_Hashtable, std::allocator >, std::__cxx11::basic_string, std::allocator >, std::allocator, std::allocator > >, std::__detail::_Identity, std::equal_to, std::allocator > >, stringtable_hash, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits >::_M_insert, std::allocator > const&, std::__detail::_AllocNode, std::allocator >, true> > > >
       0.78%  stap     stap                  [.] lexer::scan
       0.74%  cc1      cc1                   [.] _cpp_lex_direct
       0.70%  cc1      cc1                   [.] pop_scope
       0.70%  cc1      cc1                   [.] c_parser_declspecs
       0.69%  stap     libc-2.29.so          [.] _int_malloc
       0.68%  cc1      cc1                   [.] htab_find_slot
       0.68%  cc1      [kernel.vmlinux]      [k] prepare_exit_to_usermode
       0.64%  cc1      [kernel.vmlinux]      [k] clear_page_erms
  [root@quaco testsuite]#

And now only what happens in slices demarcated by those start/end SDT
events:

  [root@quaco testsuite]# perf report --switch-on=sdt_stap:pass2__start --switch-off=sdt_stap:pass2__end | grep cycles:P -A100
  # Samples: 240  of event 'cycles:P'
  # Event count (approx.): 206491934
  #
  # Overhead  Command  Shared Object        Symbol
  # ........  .......  ...................  ................................................
  #
      38.99%  stap     stap                 [.] systemtap_session::register_library_aliases
      19.47%  stap     stap                 [.] match_key::operator<
      15.01%  stap     libc-2.29.so         [.] __memcmp_avx2_movbe
       5.19%  stap     libc-2.29.so         [.] _int_malloc
       2.50%  stap     libstdc++.so.6.0.26  [.] std::_Rb_tree_insert_and_rebalance
       2.30%  stap     stap                 [.] match_node::build_no_more
       2.07%  stap     libc-2.29.so         [.] malloc
       1.66%  stap     stap                 [.] std::_Rb_tree, std::_Select1st >, std::less, std::allocator > >::find
       1.66%  stap     stap                 [.] match_node::bind
       1.58%  stap     [kernel.vmlinux]     [k] prepare_exit_to_usermode
       1.17%  stap     [kernel.vmlinux]     [k] native_irq_return_iret
       0.87%  stap     stap                 [.] 0x0000000000032ec4
       0.77%  stap     libstdc++.so.6.0.26  [.] std::_Rb_tree_increment
       0.47%  stap     stap                 [.] std::vector >::_M_realloc_insert
       0.47%  stap     [kernel.vmlinux]     [k] get_page_from_freelist
       0.47%  stap     [kernel.vmlinux]     [k] swapgs_restore_regs_and_return_to_usermode
       0.47%  stap     [kernel.vmlinux]     [k] do_user_addr_fault
       0.46%  stap     [kernel.vmlinux]     [k] __pagevec_lru_add_fn
       0.46%  stap     stap                 [.] std::_Rb_tree, std::_Select1st >, std::less, std::allocator > >::_M_emplace_unique >
       0.42%  stap     libstdc++.so.6.0.26  [.] 0x00000000000c18fa
       0.40%  stap     [kernel.vmlinux]     [k] interrupt_entry
       0.40%  stap     [kernel.vmlinux]     [k] update_load_avg
       0.40%  stap     [kernel.vmlinux]     [k] __intel_pmu_disable_all
       0.40%  stap     [kernel.vmlinux]     [k] clear_page_erms
       0.39%  stap     [kernel.vmlinux]     [k] __mod_node_page_state
       0.39%  stap     [kernel.vmlinux]     [k] error_entry
       0.39%  stap     [kernel.vmlinux]     [k] sync_regs
       0.38%  stap     [kernel.vmlinux]     [k] __handle_mm_fault
       0.38%  stap     stap                 [.] derive_probes

  #
  # (Tip: System-wide collection from all CPUs: perf record -a)
  #
  [root@quaco testsuite]#

Cc: Adrian Hunter 
Cc: Florian Weimer 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: William Cohen 
Link: https://lkml.kernel.org/n/tip-408hvumcnyn93a0auihnawew@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix typos / broken sentences

2019-07-02T19:08:16+00:00

- Fix a typo in the man page
- Fix a tip that doesn't make any sense.

Signed-off-by: Andi Kleen 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/20190628220900.13741-1-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf time-utils: Add support for multiple explicit time intervals

2019-06-10T19:20:13+00:00

Currently only a single explicit time range is accepted. Add support for
multiple ranges separated by spaces, which requires the string to be
quoted. Update the time utils test accordingly.

Signed-off-by: Adrian Hunter 
Cc: Jin Yao 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/20190604130017.31207-20-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf time-utils: Fix --time documentation

2019-06-10T19:20:12+00:00

Correct some punctuation and spelling and correct the format to show
that the time resolution is nanoseconds not microseconds.

Signed-off-by: Adrian Hunter 
Cc: Jin Yao 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/20190604130017.31207-16-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Implement browsing of individual samples

2019-03-11T19:33:19+00:00

Now 'perf report' can show whole time periods with 'perf script', but
the user still has to find individual samples of interest manually.

It would be expensive and complicated to search for the right samples in
the whole perf file. Typically users only need to look at a small number
of samples for useful analysis.

Also the full scripts tend to show samples of all CPUs and all threads
mixed up, which can be very confusing on larger systems.

Add a new --samples option to save a small random number of samples per
hist entry.

Use a reservoir sample technique to select a representatve number of
samples.

Then allow browsing the samples using 'perf script' as part of the hist
entry context menu. This automatically adds the right filters, so only
the thread or cpu of the sample is displayed. Then we use less' search
functionality to directly jump the to the time stamp of the selected
sample.

It uses different menus for assembler and source display.  Assembler
needs xed installed and source needs debuginfo.

Currently it only supports as many samples as fit on the screen due to
some limitations in the slang ui code.

Signed-off-by: Andi Kleen 
Tested-by: Arnaldo Carvalho de Melo 
Acked-by: Jiri Olsa 
Link: http://lkml.kernel.org/r/20190311174605.GA29294@tassilo.jf.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Support time sort key

2019-03-11T19:32:31+00:00

Add a time sort key to perf report to display samples for different time
quantums separately. This allows easier analysis of workloads that
change over time, and also will allow looking at the context of samples.

% perf record ...
% perf report --sort time,overhead,symbol --time-quantum 1ms --stdio
...
     0.67%  277061.87300  [.] _dl_start
     0.50%  277061.87300  [.] f1
     0.50%  277061.87300  [.] f2
     0.33%  277061.87300  [.] main
     0.29%  277061.87300  [.] _dl_lookup_symbol_x
     0.29%  277061.87300  [.] dl_main
     0.29%  277061.87300  [.] do_lookup_x
     0.17%  277061.87300  [.] _dl_debug_initialize
     0.17%  277061.87300  [.] _dl_init_paths
     0.08%  277061.87300  [.] check_match
     0.04%  277061.87300  [.] _dl_count_modids
     1.33%  277061.87400  [.] f1
     1.33%  277061.87400  [.] f2
     1.33%  277061.87400  [.] main
     1.17%  277061.87500  [.] main
     1.08%  277061.87500  [.] f1
     1.08%  277061.87500  [.] f2
     1.00%  277061.87600  [.] main
     0.83%  277061.87600  [.] f1
     0.83%  277061.87600  [.] f2
     1.00%  277061.87700  [.] main

Committer notes:

Rename 'time' argument to hist_time() to htime to overcome this in older
distros:

  cc1: warnings being treated as errors
  util/hist.c: In function 'hist_time':
  util/hist.c:251: error: declaration of 'time' shadows a global declaration
  /usr/include/time.h:186: error: shadowed declaration is here

Signed-off-by: Andi Kleen 
Acked-by: Jiri Olsa 
Link: http://lkml.kernel.org/r/20190311144502.15423-4-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Parse time quantum

2019-03-11T14:56:03+00:00

Many workloads change over time. 'perf report' currently aggregates the
whole time range reported in perf.data.

This patch adds an option for a time quantum to quantisize the perf.data
over time.

This just adds the option, will be used in follow on patches for a time
sort key.

Signed-off-by: Andi Kleen 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20190305144758.12397-6-andi@firstfloor.org
[ Use NSEC_PER_[MU]SEC ]
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Support output in nanoseconds

2019-03-11T14:56:02+00:00

Upcoming changes add timestamp output in perf report. Add a --ns
argument similar to perf script to support nanoseconds resolution when
needed.

Signed-off-by: Andi Kleen 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20190305144758.12397-5-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools Documentation: Fix diverse typos

2018-12-17T17:56:36+00:00

Go over the tools/ files that are maintained in Arnaldo's tree and
fix common typos: half of them were in comments, the other half
in JSON files.

No change in functionality intended.

Committer notes:

This was split from a larger patch as there are code that is,
additionally, maintained outside the kernel tree, so to ease cherry
picking and/or backporting, split this into multiple patches.

In this particular case, it affects documentation, so may be interesting
to cherry pick as it is information that is presented to the user.

Signed-off-by: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20181203102200.GA104797@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Documentation average IPC and IPC coverage

2018-12-17T17:55:49+00:00

Add explanations for new columns "IPC" and "IPC coverage" in perf
documentation.

 v5:
 ---
 Update the description according to Ingo's comments.

Signed-off-by: Jin Yao 
Reviewed-by: Ingo Molnar 
Reviewed-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Kan Liang 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1543586097-27632-5-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo