For example, in an application with an expensive function implemented
with deeply nested recursive calls, the default call-graph presentation
is dominated by the different callchains within that function. By
ignoring these callees, we can collect the callchains leading into the
function and compactly identify what to blame for expensive calls.
For example, in this report the callers of garbage_collect() are
scattered across the tree:
$ perf report -d ruby 2>- | grep -m10 ^[^#]*[a-z]
22.03% ruby [.] gc_mark
--- gc_mark
|--59.40%-- mark_keyvalue
| st_foreach
| gc_mark_children
| |--99.75%-- rb_gc_mark
| | rb_vm_mark
| | gc_mark_children
| | gc_marks
| | |--99.00%-- garbage_collect
If we ignore the callees of garbage_collect(), its callers are coalesced:
$ perf report --ignore-callees garbage_collect -d ruby 2>- | grep -m10 ^[^#]*[a-z]
72.92% ruby [.] garbage_collect
--- garbage_collect
vm_xmalloc
|--47.08%-- ruby_xmalloc
| st_insert2
| rb_hash_aset
| |--98.45%-- features_index_add
| | rb_provide_feature
| | rb_require_safe
| | vm_call_method
Signed-off-by: Greg Price <price@mit.edu>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20130623031720.GW22203@biohazard-cafe.mit.edu
Link: http://lkml.kernel.org/r/20130708115746.GO22203@biohazard-cafe.mit.edu
Cc: Fengguang Wu <fengguang.wu@intel.com>
[ remove spaces at beginning of line, reported by Fengguang Wu ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The CPU map is in an "empty" (or not-applicable) state when monitoring
specific threads.
cpu_map__all() returns true if the CPU map is in this empty state (i.e
for the 'empty_cpu_map' or if we created the map via
cpu_map__dummy_new().
The name, cpu_map__all(), is misleading, because even when monitoring
all CPUs, (eg: perf record -a), cpu_map__all() returns false.
Rename cpu_map__all() to cpu_map__empty().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20130523012620.GA27733@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The tag of the perf version is wrongly determined, always the latest tag
is taken regardless of the HEAD commit:
$ perf --version
perf version 3.9.rc8.gd7f5d3
$ git describe d7f5d3
v3.9-rc7-154-gd7f5d33
$ head -n 4 Makefile
VERSION = 3
PATCHLEVEL = 9
SUBLEVEL = 0
EXTRAVERSION = -rc7
In other cases no tag might be found.
This patch fixes this.
This new implementation handles also the case if there are no tags at
all found in the git repo but there is a commit id.
Signed-off-by: Robert Richter <robert.richter@calxeda.com>
Link: http://lkml.kernel.org/r/1368006214-12912-1-git-send-email-rric@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When "perf record" was used on a large machine with a lot of CPUs, the
perf post-processing time (the time after the workload was done until
the perf command itself exited) could take a lot of minutes and even
hours depending on how large the resulting perf.data file was.
While running AIM7 1500-user high_systime workload on a 80-core x86-64
system with a 3.9 kernel (with only the -s -a options used), the
workload itself took about 2 minutes to run and the perf.data file had a
size of 1108.746 MB. However, the post-processing step took more than 10
minutes.
With a gprof-profiled perf binary, the time spent by perf was as
follows:
% cumulative self self total
time seconds seconds calls s/call s/call name
96.90 822.10 822.10 192156 0.00 0.00 dsos__find
0.81 828.96 6.86 172089958 0.00 0.00 rb_next
0.41 832.44 3.48 48539289 0.00 0.00 rb_erase
So 97% (822 seconds) of the time was spent in a single dsos_find()
function. After analyzing the call-graph data below:
-----------------------------------------------
0.00 822.12 192156/192156 map__new [6]
[7] 96.9 0.00 822.12 192156 vdso__dso_findnew [7]
822.10 0.00 192156/192156 dsos__find [8]
0.01 0.00 192156/192156 dsos__add [62]
0.01 0.00 192156/192366 dso__new [61]
0.00 0.00 1/45282525 memdup [31]
0.00 0.00 192156/192230 dso__set_long_name [91]
-----------------------------------------------
822.10 0.00 192156/192156 vdso__dso_findnew [7]
[8] 96.9 822.10 0.00 192156 dsos__find [8]
-----------------------------------------------
It was found that the vdso__dso_findnew() function failed to locate
VDSO__MAP_NAME ("[vdso]") in the dso list and have to insert a new
entry at the end for 192156 times. This problem is due to the fact that
there are 2 types of name in the dso entry - short name and long name.
The initial dso__new() adds "[vdso]" to both the short and long names.
After that, vdso__dso_findnew() modifies the long name to something
like /tmp/perf-vdso.so-NoXkDj. The dsos__find() function only compares
the long name. As a result, the same vdso entry is duplicated many
time in the dso list. This bug increases memory consumption as well
as slows the symbol processing time to a crawl.
To resolve this problem, the dsos__find() function interface was
modified to enable searching either the long name or the short
name. The vdso__dso_findnew() will now search only the short name
while the other call sites search for the long name as before.
With this change, the cpu time of perf was reduced from 848.38s to
15.77s and dsos__find() only accounted for 0.06% of the total time.
0.06 15.73 0.01 192151 0.00 0.00 dsos__find
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: "Chandramouleeswaran, Aswin" <aswin@hp.com>
Cc: "Norton, Scott J" <scott.norton@hp.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1368110568-64714-1-git-send-email-Waiman.Long@hp.com
[ replaced TRUE/FALSE with stdbool.h equivalents, fixing builds where
those macros are not present (NO_LIBPYTHON=1 NO_LIBPERL=1), fix from Jiri Olsa ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
per realloc above the length of the buffer is alloc_size, not BUFSIZ.
Adjust length per size as done for buf start.
Addresses some valgrind complaints:
==1870== Syscall param read(buf) points to unaddressable byte(s)
==1870== at 0x4E3F610: __read_nocancel (in /lib64/libpthread-2.14.90.so)
==1870== by 0x44AEE1: event_format__new (unistd.h:45)
==1870== by 0x44B025: perf_evsel__newtp (evsel.c:158)
==1870== by 0x451919: add_tracepoint_event (parse-events.c:395)
==1870== by 0x479815: parse_events_parse (parse-events.y:292)
==1870== by 0x45463A: parse_events_option (parse-events.c:861)
==1870== by 0x44FEE4: get_value (parse-options.c:113)
==1870== by 0x450767: parse_options_step (parse-options.c:192)
==1870== by 0x450C40: parse_options (parse-options.c:422)
==1870== by 0x42735F: cmd_record (builtin-record.c:918)
==1870== by 0x419D72: run_builtin (perf.c:319)
==1870== by 0x4195F2: main (perf.c:376)
==1870== Address 0xcffebf0 is 0 bytes after a block of size 8,192 alloc'd
==1870== at 0x4C2A62F: malloc (vg_replace_malloc.c:270)
==1870== by 0x4C2A7A3: realloc (vg_replace_malloc.c:662)
==1870== by 0x44AF07: event_format__new (evsel.c:121)
==1870== by 0x44B025: perf_evsel__newtp (evsel.c:158)
==1870== by 0x451919: add_tracepoint_event (parse-events.c:395)
==1870== by 0x479815: parse_events_parse (parse-events.y:292)
==1870== by 0x45463A: parse_events_option (parse-events.c:861)
==1870== by 0x44FEE4: get_value (parse-options.c:113)
==1870== by 0x450767: parse_options_step (parse-options.c:192)
==1870== by 0x450C40: parse_options (parse-options.c:422)
==1870== by 0x42735F: cmd_record (builtin-record.c:918)
==1870== by 0x419D72: run_builtin (perf.c:319)
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1372793245-4136-2-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently we have symbol_conf.exclude_other being set as true every time
so the -x/--exclude-other has nothing to do.
Also we have no way to see the data with symbol_conf.exclude_other being
false which is useful sometimes.
Fixing it by making symbol_conf.exclude_other false by default.
1) Example without -x option:
$ perf report -i perf.data.delete -p perf_session__delete -s parent
+ 99.91% [other]
+ 0.08% perf_session__delete
+ 0.00% perf_session__delete_dead_threads
+ 0.00% perf_session__delete_threads
2) Example with -x option:
$ ./perf report -i perf.data.delete -p perf_session__delete -s parent -x
+ 96.22% perf_session__delete
+ 1.89% perf_session__delete_dead_threads
+ 1.89% perf_session__delete_threads
In Example 1) we get the sorted out data together with the rest
"[other]". This could help us estimate how much time we spent in the
sorted data.
In Example 2) the total is just the sorted data.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-sg8fvu0fyqohf9ur9l38lhkw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When perf tries to start a workload, it relies on a pipe which the
workload was blocked for reading. After closing the pipe on the parent,
the workload (child) can start the actual work via exec().
However, if another process was forked after creating a workload, this
mechanism cannot work since the other process (child) also inherits the
pipe, so that closing the pipe in parent cannot unblock the workload.
Fix it by using explicit write call can then closing it.
For similar reason, the pipe fd on parent should be marked as CLOEXEC so
that it can be closed after another child exec'ed.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1372230862-15861-13-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>