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1perf-report(1)
2==============
3
4NAME
5----
6perf-report - Read perf.data (created by perf record) and display the profile
7
8SYNOPSIS
9--------
10[verse]
11'perf report' [-i <file> | --input=file]
12
13DESCRIPTION
14-----------
15This command displays the performance counter profile information recorded
16via perf record.
17
18OPTIONS
19-------
20-i::
21--input=::
22 Input file name. (default: perf.data unless stdin is a fifo)
23
24-v::
25--verbose::
26 Be more verbose. (show symbol address, etc)
27
28-q::
29--quiet::
30 Do not show any message. (Suppress -v)
31
32-n::
33--show-nr-samples::
34 Show the number of samples for each symbol
35
36--show-cpu-utilization::
37 Show sample percentage for different cpu modes.
38
39-T::
40--threads::
41 Show per-thread event counters. The input data file should be recorded
42 with -s option.
43-c::
44--comms=::
45 Only consider symbols in these comms. CSV that understands
46 file://filename entries. This option will affect the percentage of
47 the overhead column. See --percentage for more info.
48--pid=::
49 Only show events for given process ID (comma separated list).
50
51--tid=::
52 Only show events for given thread ID (comma separated list).
53-d::
54--dsos=::
55 Only consider symbols in these dsos. CSV that understands
56 file://filename entries. This option will affect the percentage of
57 the overhead column. See --percentage for more info.
58-S::
59--symbols=::
60 Only consider these symbols. CSV that understands
61 file://filename entries. This option will affect the percentage of
62 the overhead column. See --percentage for more info.
63
64--symbol-filter=::
65 Only show symbols that match (partially) with this filter.
66
67-U::
68--hide-unresolved::
69 Only display entries resolved to a symbol.
70
71-s::
72--sort=::
73 Sort histogram entries by given key(s) - multiple keys can be specified
74 in CSV format. Following sort keys are available:
75 pid, comm, dso, symbol, parent, cpu, socket, srcline, weight,
76 local_weight, cgroup_id.
77
78 Each key has following meaning:
79
80 - comm: command (name) of the task which can be read via /proc/<pid>/comm
81 - pid: command and tid of the task
82 - dso: name of library or module executed at the time of sample
83 - dso_size: size of library or module executed at the time of sample
84 - symbol: name of function executed at the time of sample
85 - symbol_size: size of function executed at the time of sample
86 - parent: name of function matched to the parent regex filter. Unmatched
87 entries are displayed as "[other]".
88 - cpu: cpu number the task ran at the time of sample
89 - socket: processor socket number the task ran at the time of sample
90 - srcline: filename and line number executed at the time of sample. The
91 DWARF debugging info must be provided.
92 - srcfile: file name of the source file of the same. Requires dwarf
93 information.
94 - weight: Event specific weight, e.g. memory latency or transaction
95 abort cost. This is the global weight.
96 - local_weight: Local weight version of the weight above.
97 - cgroup_id: ID derived from cgroup namespace device and inode numbers.
98 - transaction: Transaction abort flags.
99 - overhead: Overhead percentage of sample
100 - overhead_sys: Overhead percentage of sample running in system mode
101 - overhead_us: Overhead percentage of sample running in user mode
102 - overhead_guest_sys: Overhead percentage of sample running in system mode
103 on guest machine
104 - overhead_guest_us: Overhead percentage of sample running in user mode on
105 guest machine
106 - sample: Number of sample
107 - period: Raw number of event count of sample
108
109 By default, comm, dso and symbol keys are used.
110 (i.e. --sort comm,dso,symbol)
111
112 If --branch-stack option is used, following sort keys are also
113 available:
114
115 - dso_from: name of library or module branched from
116 - dso_to: name of library or module branched to
117 - symbol_from: name of function branched from
118 - symbol_to: name of function branched to
119 - srcline_from: source file and line branched from
120 - srcline_to: source file and line branched to
121 - mispredict: "N" for predicted branch, "Y" for mispredicted branch
122 - in_tx: branch in TSX transaction
123 - abort: TSX transaction abort.
124 - cycles: Cycles in basic block
125
126 And default sort keys are changed to comm, dso_from, symbol_from, dso_to
127 and symbol_to, see '--branch-stack'.
128
129 If the --mem-mode option is used, the following sort keys are also available
130 (incompatible with --branch-stack):
131 symbol_daddr, dso_daddr, locked, tlb, mem, snoop, dcacheline.
132
133 - symbol_daddr: name of data symbol being executed on at the time of sample
134 - dso_daddr: name of library or module containing the data being executed
135 on at the time of the sample
136 - locked: whether the bus was locked at the time of the sample
137 - tlb: type of tlb access for the data at the time of the sample
138 - mem: type of memory access for the data at the time of the sample
139 - snoop: type of snoop (if any) for the data at the time of the sample
140 - dcacheline: the cacheline the data address is on at the time of the sample
141 - phys_daddr: physical address of data being executed on at the time of sample
142
143 And the default sort keys are changed to local_weight, mem, sym, dso,
144 symbol_daddr, dso_daddr, snoop, tlb, locked, see '--mem-mode'.
145
146 If the data file has tracepoint event(s), following (dynamic) sort keys
147 are also available:
148 trace, trace_fields, [<event>.]<field>[/raw]
149
150 - trace: pretty printed trace output in a single column
151 - trace_fields: fields in tracepoints in separate columns
152 - <field name>: optional event and field name for a specific field
153
154 The last form consists of event and field names. If event name is
155 omitted, it searches all events for matching field name. The matched
156 field will be shown only for the event has the field. The event name
157 supports substring match so user doesn't need to specify full subsystem
158 and event name everytime. For example, 'sched:sched_switch' event can
159 be shortened to 'switch' as long as it's not ambiguous. Also event can
160 be specified by its index (starting from 1) preceded by the '%'.
161 So '%1' is the first event, '%2' is the second, and so on.
162
163 The field name can have '/raw' suffix which disables pretty printing
164 and shows raw field value like hex numbers. The --raw-trace option
165 has the same effect for all dynamic sort keys.
166
167 The default sort keys are changed to 'trace' if all events in the data
168 file are tracepoint.
169
170-F::
171--fields=::
172 Specify output field - multiple keys can be specified in CSV format.
173 Following fields are available:
174 overhead, overhead_sys, overhead_us, overhead_children, sample and period.
175 Also it can contain any sort key(s).
176
177 By default, every sort keys not specified in -F will be appended
178 automatically.
179
180 If the keys starts with a prefix '+', then it will append the specified
181 field(s) to the default field order. For example: perf report -F +period,sample.
182
183-p::
184--parent=<regex>::
185 A regex filter to identify parent. The parent is a caller of this
186 function and searched through the callchain, thus it requires callchain
187 information recorded. The pattern is in the extended regex format and
188 defaults to "\^sys_|^do_page_fault", see '--sort parent'.
189
190-x::
191--exclude-other::
192 Only display entries with parent-match.
193
194-w::
195--column-widths=<width[,width...]>::
196 Force each column width to the provided list, for large terminal
197 readability. 0 means no limit (default behavior).
198
199-t::
200--field-separator=::
201 Use a special separator character and don't pad with spaces, replacing
202 all occurrences of this separator in symbol names (and other output)
203 with a '.' character, that thus it's the only non valid separator.
204
205-D::
206--dump-raw-trace::
207 Dump raw trace in ASCII.
208
209-g::
210--call-graph=<print_type,threshold[,print_limit],order,sort_key[,branch],value>::
211 Display call chains using type, min percent threshold, print limit,
212 call order, sort key, optional branch and value. Note that ordering
213 is not fixed so any parameter can be given in an arbitrary order.
214 One exception is the print_limit which should be preceded by threshold.
215
216 print_type can be either:
217 - flat: single column, linear exposure of call chains.
218 - graph: use a graph tree, displaying absolute overhead rates. (default)
219 - fractal: like graph, but displays relative rates. Each branch of
220 the tree is considered as a new profiled object.
221 - folded: call chains are displayed in a line, separated by semicolons
222 - none: disable call chain display.
223
224 threshold is a percentage value which specifies a minimum percent to be
225 included in the output call graph. Default is 0.5 (%).
226
227 print_limit is only applied when stdio interface is used. It's to limit
228 number of call graph entries in a single hist entry. Note that it needs
229 to be given after threshold (but not necessarily consecutive).
230 Default is 0 (unlimited).
231
232 order can be either:
233 - callee: callee based call graph.
234 - caller: inverted caller based call graph.
235 Default is 'caller' when --children is used, otherwise 'callee'.
236
237 sort_key can be:
238 - function: compare on functions (default)
239 - address: compare on individual code addresses
240 - srcline: compare on source filename and line number
241
242 branch can be:
243 - branch: include last branch information in callgraph when available.
244 Usually more convenient to use --branch-history for this.
245
246 value can be:
247 - percent: diplay overhead percent (default)
248 - period: display event period
249 - count: display event count
250
251--children::
252 Accumulate callchain of children to parent entry so that then can
253 show up in the output. The output will have a new "Children" column
254 and will be sorted on the data. It requires callchains are recorded.
255 See the `overhead calculation' section for more details. Enabled by
256 default, disable with --no-children.
257
258--max-stack::
259 Set the stack depth limit when parsing the callchain, anything
260 beyond the specified depth will be ignored. This is a trade-off
261 between information loss and faster processing especially for
262 workloads that can have a very long callchain stack.
263 Note that when using the --itrace option the synthesized callchain size
264 will override this value if the synthesized callchain size is bigger.
265
266 Default: 127
267
268-G::
269--inverted::
270 alias for inverted caller based call graph.
271
272--ignore-callees=<regex>::
273 Ignore callees of the function(s) matching the given regex.
274 This has the effect of collecting the callers of each such
275 function into one place in the call-graph tree.
276
277--pretty=<key>::
278 Pretty printing style. key: normal, raw
279
280--stdio:: Use the stdio interface.
281
282--stdio-color::
283 'always', 'never' or 'auto', allowing configuring color output
284 via the command line, in addition to via "color.ui" .perfconfig.
285 Use '--stdio-color always' to generate color even when redirecting
286 to a pipe or file. Using just '--stdio-color' is equivalent to
287 using 'always'.
288
289--tui:: Use the TUI interface, that is integrated with annotate and allows
290 zooming into DSOs or threads, among other features. Use of --tui
291 requires a tty, if one is not present, as when piping to other
292 commands, the stdio interface is used.
293
294--gtk:: Use the GTK2 interface.
295
296-k::
297--vmlinux=<file>::
298 vmlinux pathname
299
300--ignore-vmlinux::
301 Ignore vmlinux files.
302
303--kallsyms=<file>::
304 kallsyms pathname
305
306-m::
307--modules::
308 Load module symbols. WARNING: This should only be used with -k and
309 a LIVE kernel.
310
311-f::
312--force::
313 Don't do ownership validation.
314
315--symfs=<directory>::
316 Look for files with symbols relative to this directory.
317
318-C::
319--cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
320 be provided as a comma-separated list with no space: 0,1. Ranges of
321 CPUs are specified with -: 0-2. Default is to report samples on all
322 CPUs.
323
324-M::
325--disassembler-style=:: Set disassembler style for objdump.
326
327--source::
328 Interleave source code with assembly code. Enabled by default,
329 disable with --no-source.
330
331--asm-raw::
332 Show raw instruction encoding of assembly instructions.
333
334--show-total-period:: Show a column with the sum of periods.
335
336-I::
337--show-info::
338 Display extended information about the perf.data file. This adds
339 information which may be very large and thus may clutter the display.
340 It currently includes: cpu and numa topology of the host system.
341
342-b::
343--branch-stack::
344 Use the addresses of sampled taken branches instead of the instruction
345 address to build the histograms. To generate meaningful output, the
346 perf.data file must have been obtained using perf record -b or
347 perf record --branch-filter xxx where xxx is a branch filter option.
348 perf report is able to auto-detect whether a perf.data file contains
349 branch stacks and it will automatically switch to the branch view mode,
350 unless --no-branch-stack is used.
351
352--branch-history::
353 Add the addresses of sampled taken branches to the callstack.
354 This allows to examine the path the program took to each sample.
355 The data collection must have used -b (or -j) and -g.
356
357--objdump=<path>::
358 Path to objdump binary.
359
360--group::
361 Show event group information together. It forces group output also
362 if there are no groups defined in data file.
363
364--demangle::
365 Demangle symbol names to human readable form. It's enabled by default,
366 disable with --no-demangle.
367
368--demangle-kernel::
369 Demangle kernel symbol names to human readable form (for C++ kernels).
370
371--mem-mode::
372 Use the data addresses of samples in addition to instruction addresses
373 to build the histograms. To generate meaningful output, the perf.data
374 file must have been obtained using perf record -d -W and using a
375 special event -e cpu/mem-loads/p or -e cpu/mem-stores/p. See
376 'perf mem' for simpler access.
377
378--percent-limit::
379 Do not show entries which have an overhead under that percent.
380 (Default: 0). Note that this option also sets the percent limit (threshold)
381 of callchains. However the default value of callchain threshold is
382 different than the default value of hist entries. Please see the
383 --call-graph option for details.
384
385--percentage::
386 Determine how to display the overhead percentage of filtered entries.
387 Filters can be applied by --comms, --dsos and/or --symbols options and
388 Zoom operations on the TUI (thread, dso, etc).
389
390 "relative" means it's relative to filtered entries only so that the
391 sum of shown entries will be always 100%. "absolute" means it retains
392 the original value before and after the filter is applied.
393
394--header::
395 Show header information in the perf.data file. This includes
396 various information like hostname, OS and perf version, cpu/mem
397 info, perf command line, event list and so on. Currently only
398 --stdio output supports this feature.
399
400--header-only::
401 Show only perf.data header (forces --stdio).
402
403--time::
404 Only analyze samples within given time window: <start>,<stop>. Times
405 have the format seconds.microseconds. If start is not given (i.e., time
406 string is ',x.y') then analysis starts at the beginning of the file. If
407 stop time is not given (i.e, time string is 'x.y,') then analysis goes
408 to end of file.
409
410 Also support time percent with multiple time range. Time string is
411 'a%/n,b%/m,...' or 'a%-b%,c%-%d,...'.
412
413 For example:
414 Select the second 10% time slice:
415
416 perf report --time 10%/2
417
418 Select from 0% to 10% time slice:
419
420 perf report --time 0%-10%
421
422 Select the first and second 10% time slices:
423
424 perf report --time 10%/1,10%/2
425
426 Select from 0% to 10% and 30% to 40% slices:
427
428 perf report --time 0%-10%,30%-40%
429
430--itrace::
431 Options for decoding instruction tracing data. The options are:
432
433include::itrace.txt[]
434
435 To disable decoding entirely, use --no-itrace.
436
437--full-source-path::
438 Show the full path for source files for srcline output.
439
440--show-ref-call-graph::
441 When multiple events are sampled, it may not be needed to collect
442 callgraphs for all of them. The sample sites are usually nearby,
443 and it's enough to collect the callgraphs on a reference event.
444 So user can use "call-graph=no" event modifier to disable callgraph
445 for other events to reduce the overhead.
446 However, perf report cannot show callgraphs for the event which
447 disable the callgraph.
448 This option extends the perf report to show reference callgraphs,
449 which collected by reference event, in no callgraph event.
450
451--socket-filter::
452 Only report the samples on the processor socket that match with this filter
453
454--raw-trace::
455 When displaying traceevent output, do not use print fmt or plugins.
456
457--hierarchy::
458 Enable hierarchical output.
459
460--inline::
461 If a callgraph address belongs to an inlined function, the inline stack
462 will be printed. Each entry is function name or file/line. Enabled by
463 default, disable with --no-inline.
464
465--mmaps::
466 Show --tasks output plus mmap information in a format similar to
467 /proc/<PID>/maps.
468
469 Please note that not all mmaps are stored, options affecting which ones
470 are include 'perf record --data', for instance.
471
472--stats::
473 Display overall events statistics without any further processing.
474 (like the one at the end of the perf report -D command)
475
476--tasks::
477 Display monitored tasks stored in perf data. Displaying pid/tid/ppid
478 plus the command string aligned to distinguish parent and child tasks.
479
480include::callchain-overhead-calculation.txt[]
481
482SEE ALSO
483--------
484linkperf:perf-stat[1], linkperf:perf-annotate[1], linkperf:perf-record[1]
1perf-report(1)
2==============
3
4NAME
5----
6perf-report - Read perf.data (created by perf record) and display the profile
7
8SYNOPSIS
9--------
10[verse]
11'perf report' [-i <file> | --input=file]
12
13DESCRIPTION
14-----------
15This command displays the performance counter profile information recorded
16via perf record.
17
18OPTIONS
19-------
20-i::
21--input=::
22 Input file name. (default: perf.data unless stdin is a fifo)
23
24-v::
25--verbose::
26 Be more verbose. (show symbol address, etc)
27
28-q::
29--quiet::
30 Do not show any message. (Suppress -v)
31
32-n::
33--show-nr-samples::
34 Show the number of samples for each symbol
35
36--show-cpu-utilization::
37 Show sample percentage for different cpu modes.
38
39-T::
40--threads::
41 Show per-thread event counters. The input data file should be recorded
42 with -s option.
43-c::
44--comms=::
45 Only consider symbols in these comms. CSV that understands
46 file://filename entries. This option will affect the percentage of
47 the overhead column. See --percentage for more info.
48--pid=::
49 Only show events for given process ID (comma separated list).
50
51--tid=::
52 Only show events for given thread ID (comma separated list).
53-d::
54--dsos=::
55 Only consider symbols in these dsos. CSV that understands
56 file://filename entries. This option will affect the percentage of
57 the overhead column. See --percentage for more info.
58-S::
59--symbols=::
60 Only consider these symbols. CSV that understands
61 file://filename entries. This option will affect the percentage of
62 the overhead column. See --percentage for more info.
63
64--symbol-filter=::
65 Only show symbols that match (partially) with this filter.
66
67-U::
68--hide-unresolved::
69 Only display entries resolved to a symbol.
70
71-s::
72--sort=::
73 Sort histogram entries by given key(s) - multiple keys can be specified
74 in CSV format. Following sort keys are available:
75 pid, comm, dso, symbol, parent, cpu, socket, srcline, weight,
76 local_weight, cgroup_id.
77
78 Each key has following meaning:
79
80 - comm: command (name) of the task which can be read via /proc/<pid>/comm
81 - pid: command and tid of the task
82 - dso: name of library or module executed at the time of sample
83 - dso_size: size of library or module executed at the time of sample
84 - symbol: name of function executed at the time of sample
85 - symbol_size: size of function executed at the time of sample
86 - parent: name of function matched to the parent regex filter. Unmatched
87 entries are displayed as "[other]".
88 - cpu: cpu number the task ran at the time of sample
89 - socket: processor socket number the task ran at the time of sample
90 - srcline: filename and line number executed at the time of sample. The
91 DWARF debugging info must be provided.
92 - srcfile: file name of the source file of the samples. Requires dwarf
93 information.
94 - weight: Event specific weight, e.g. memory latency or transaction
95 abort cost. This is the global weight.
96 - local_weight: Local weight version of the weight above.
97 - cgroup_id: ID derived from cgroup namespace device and inode numbers.
98 - transaction: Transaction abort flags.
99 - overhead: Overhead percentage of sample
100 - overhead_sys: Overhead percentage of sample running in system mode
101 - overhead_us: Overhead percentage of sample running in user mode
102 - overhead_guest_sys: Overhead percentage of sample running in system mode
103 on guest machine
104 - overhead_guest_us: Overhead percentage of sample running in user mode on
105 guest machine
106 - sample: Number of sample
107 - period: Raw number of event count of sample
108 - time: Separate the samples by time stamp with the resolution specified by
109 --time-quantum (default 100ms). Specify with overhead and before it.
110
111 By default, comm, dso and symbol keys are used.
112 (i.e. --sort comm,dso,symbol)
113
114 If --branch-stack option is used, following sort keys are also
115 available:
116
117 - dso_from: name of library or module branched from
118 - dso_to: name of library or module branched to
119 - symbol_from: name of function branched from
120 - symbol_to: name of function branched to
121 - srcline_from: source file and line branched from
122 - srcline_to: source file and line branched to
123 - mispredict: "N" for predicted branch, "Y" for mispredicted branch
124 - in_tx: branch in TSX transaction
125 - abort: TSX transaction abort.
126 - cycles: Cycles in basic block
127
128 And default sort keys are changed to comm, dso_from, symbol_from, dso_to
129 and symbol_to, see '--branch-stack'.
130
131 When the sort key symbol is specified, columns "IPC" and "IPC Coverage"
132 are enabled automatically. Column "IPC" reports the average IPC per function
133 and column "IPC coverage" reports the percentage of instructions with
134 sampled IPC in this function. IPC means Instruction Per Cycle. If it's low,
135 it indicates there may be a performance bottleneck when the function is
136 executed, such as a memory access bottleneck. If a function has high overhead
137 and low IPC, it's worth further analyzing it to optimize its performance.
138
139 If the --mem-mode option is used, the following sort keys are also available
140 (incompatible with --branch-stack):
141 symbol_daddr, dso_daddr, locked, tlb, mem, snoop, dcacheline.
142
143 - symbol_daddr: name of data symbol being executed on at the time of sample
144 - dso_daddr: name of library or module containing the data being executed
145 on at the time of the sample
146 - locked: whether the bus was locked at the time of the sample
147 - tlb: type of tlb access for the data at the time of the sample
148 - mem: type of memory access for the data at the time of the sample
149 - snoop: type of snoop (if any) for the data at the time of the sample
150 - dcacheline: the cacheline the data address is on at the time of the sample
151 - phys_daddr: physical address of data being executed on at the time of sample
152
153 And the default sort keys are changed to local_weight, mem, sym, dso,
154 symbol_daddr, dso_daddr, snoop, tlb, locked, see '--mem-mode'.
155
156 If the data file has tracepoint event(s), following (dynamic) sort keys
157 are also available:
158 trace, trace_fields, [<event>.]<field>[/raw]
159
160 - trace: pretty printed trace output in a single column
161 - trace_fields: fields in tracepoints in separate columns
162 - <field name>: optional event and field name for a specific field
163
164 The last form consists of event and field names. If event name is
165 omitted, it searches all events for matching field name. The matched
166 field will be shown only for the event has the field. The event name
167 supports substring match so user doesn't need to specify full subsystem
168 and event name everytime. For example, 'sched:sched_switch' event can
169 be shortened to 'switch' as long as it's not ambiguous. Also event can
170 be specified by its index (starting from 1) preceded by the '%'.
171 So '%1' is the first event, '%2' is the second, and so on.
172
173 The field name can have '/raw' suffix which disables pretty printing
174 and shows raw field value like hex numbers. The --raw-trace option
175 has the same effect for all dynamic sort keys.
176
177 The default sort keys are changed to 'trace' if all events in the data
178 file are tracepoint.
179
180-F::
181--fields=::
182 Specify output field - multiple keys can be specified in CSV format.
183 Following fields are available:
184 overhead, overhead_sys, overhead_us, overhead_children, sample and period.
185 Also it can contain any sort key(s).
186
187 By default, every sort keys not specified in -F will be appended
188 automatically.
189
190 If the keys starts with a prefix '+', then it will append the specified
191 field(s) to the default field order. For example: perf report -F +period,sample.
192
193-p::
194--parent=<regex>::
195 A regex filter to identify parent. The parent is a caller of this
196 function and searched through the callchain, thus it requires callchain
197 information recorded. The pattern is in the extended regex format and
198 defaults to "\^sys_|^do_page_fault", see '--sort parent'.
199
200-x::
201--exclude-other::
202 Only display entries with parent-match.
203
204-w::
205--column-widths=<width[,width...]>::
206 Force each column width to the provided list, for large terminal
207 readability. 0 means no limit (default behavior).
208
209-t::
210--field-separator=::
211 Use a special separator character and don't pad with spaces, replacing
212 all occurrences of this separator in symbol names (and other output)
213 with a '.' character, that thus it's the only non valid separator.
214
215-D::
216--dump-raw-trace::
217 Dump raw trace in ASCII.
218
219-g::
220--call-graph=<print_type,threshold[,print_limit],order,sort_key[,branch],value>::
221 Display call chains using type, min percent threshold, print limit,
222 call order, sort key, optional branch and value. Note that ordering
223 is not fixed so any parameter can be given in an arbitrary order.
224 One exception is the print_limit which should be preceded by threshold.
225
226 print_type can be either:
227 - flat: single column, linear exposure of call chains.
228 - graph: use a graph tree, displaying absolute overhead rates. (default)
229 - fractal: like graph, but displays relative rates. Each branch of
230 the tree is considered as a new profiled object.
231 - folded: call chains are displayed in a line, separated by semicolons
232 - none: disable call chain display.
233
234 threshold is a percentage value which specifies a minimum percent to be
235 included in the output call graph. Default is 0.5 (%).
236
237 print_limit is only applied when stdio interface is used. It's to limit
238 number of call graph entries in a single hist entry. Note that it needs
239 to be given after threshold (but not necessarily consecutive).
240 Default is 0 (unlimited).
241
242 order can be either:
243 - callee: callee based call graph.
244 - caller: inverted caller based call graph.
245 Default is 'caller' when --children is used, otherwise 'callee'.
246
247 sort_key can be:
248 - function: compare on functions (default)
249 - address: compare on individual code addresses
250 - srcline: compare on source filename and line number
251
252 branch can be:
253 - branch: include last branch information in callgraph when available.
254 Usually more convenient to use --branch-history for this.
255
256 value can be:
257 - percent: display overhead percent (default)
258 - period: display event period
259 - count: display event count
260
261--children::
262 Accumulate callchain of children to parent entry so that then can
263 show up in the output. The output will have a new "Children" column
264 and will be sorted on the data. It requires callchains are recorded.
265 See the `overhead calculation' section for more details. Enabled by
266 default, disable with --no-children.
267
268--max-stack::
269 Set the stack depth limit when parsing the callchain, anything
270 beyond the specified depth will be ignored. This is a trade-off
271 between information loss and faster processing especially for
272 workloads that can have a very long callchain stack.
273 Note that when using the --itrace option the synthesized callchain size
274 will override this value if the synthesized callchain size is bigger.
275
276 Default: 127
277
278-G::
279--inverted::
280 alias for inverted caller based call graph.
281
282--ignore-callees=<regex>::
283 Ignore callees of the function(s) matching the given regex.
284 This has the effect of collecting the callers of each such
285 function into one place in the call-graph tree.
286
287--pretty=<key>::
288 Pretty printing style. key: normal, raw
289
290--stdio:: Use the stdio interface.
291
292--stdio-color::
293 'always', 'never' or 'auto', allowing configuring color output
294 via the command line, in addition to via "color.ui" .perfconfig.
295 Use '--stdio-color always' to generate color even when redirecting
296 to a pipe or file. Using just '--stdio-color' is equivalent to
297 using 'always'.
298
299--tui:: Use the TUI interface, that is integrated with annotate and allows
300 zooming into DSOs or threads, among other features. Use of --tui
301 requires a tty, if one is not present, as when piping to other
302 commands, the stdio interface is used.
303
304--gtk:: Use the GTK2 interface.
305
306-k::
307--vmlinux=<file>::
308 vmlinux pathname
309
310--ignore-vmlinux::
311 Ignore vmlinux files.
312
313--kallsyms=<file>::
314 kallsyms pathname
315
316-m::
317--modules::
318 Load module symbols. WARNING: This should only be used with -k and
319 a LIVE kernel.
320
321-f::
322--force::
323 Don't do ownership validation.
324
325--symfs=<directory>::
326 Look for files with symbols relative to this directory.
327
328-C::
329--cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
330 be provided as a comma-separated list with no space: 0,1. Ranges of
331 CPUs are specified with -: 0-2. Default is to report samples on all
332 CPUs.
333
334-M::
335--disassembler-style=:: Set disassembler style for objdump.
336
337--source::
338 Interleave source code with assembly code. Enabled by default,
339 disable with --no-source.
340
341--asm-raw::
342 Show raw instruction encoding of assembly instructions.
343
344--show-total-period:: Show a column with the sum of periods.
345
346-I::
347--show-info::
348 Display extended information about the perf.data file. This adds
349 information which may be very large and thus may clutter the display.
350 It currently includes: cpu and numa topology of the host system.
351
352-b::
353--branch-stack::
354 Use the addresses of sampled taken branches instead of the instruction
355 address to build the histograms. To generate meaningful output, the
356 perf.data file must have been obtained using perf record -b or
357 perf record --branch-filter xxx where xxx is a branch filter option.
358 perf report is able to auto-detect whether a perf.data file contains
359 branch stacks and it will automatically switch to the branch view mode,
360 unless --no-branch-stack is used.
361
362--branch-history::
363 Add the addresses of sampled taken branches to the callstack.
364 This allows to examine the path the program took to each sample.
365 The data collection must have used -b (or -j) and -g.
366
367--objdump=<path>::
368 Path to objdump binary.
369
370--group::
371 Show event group information together. It forces group output also
372 if there are no groups defined in data file.
373
374--demangle::
375 Demangle symbol names to human readable form. It's enabled by default,
376 disable with --no-demangle.
377
378--demangle-kernel::
379 Demangle kernel symbol names to human readable form (for C++ kernels).
380
381--mem-mode::
382 Use the data addresses of samples in addition to instruction addresses
383 to build the histograms. To generate meaningful output, the perf.data
384 file must have been obtained using perf record -d -W and using a
385 special event -e cpu/mem-loads/p or -e cpu/mem-stores/p. See
386 'perf mem' for simpler access.
387
388--percent-limit::
389 Do not show entries which have an overhead under that percent.
390 (Default: 0). Note that this option also sets the percent limit (threshold)
391 of callchains. However the default value of callchain threshold is
392 different than the default value of hist entries. Please see the
393 --call-graph option for details.
394
395--percentage::
396 Determine how to display the overhead percentage of filtered entries.
397 Filters can be applied by --comms, --dsos and/or --symbols options and
398 Zoom operations on the TUI (thread, dso, etc).
399
400 "relative" means it's relative to filtered entries only so that the
401 sum of shown entries will be always 100%. "absolute" means it retains
402 the original value before and after the filter is applied.
403
404--header::
405 Show header information in the perf.data file. This includes
406 various information like hostname, OS and perf version, cpu/mem
407 info, perf command line, event list and so on. Currently only
408 --stdio output supports this feature.
409
410--header-only::
411 Show only perf.data header (forces --stdio).
412
413--time::
414 Only analyze samples within given time window: <start>,<stop>. Times
415 have the format seconds.nanoseconds. If start is not given (i.e. time
416 string is ',x.y') then analysis starts at the beginning of the file. If
417 stop time is not given (i.e. time string is 'x.y,') then analysis goes
418 to end of file. Multiple ranges can be separated by spaces, which
419 requires the argument to be quoted e.g. --time "1234.567,1234.789 1235,"
420
421 Also support time percent with multiple time ranges. Time string is
422 'a%/n,b%/m,...' or 'a%-b%,c%-%d,...'.
423
424 For example:
425 Select the second 10% time slice:
426
427 perf report --time 10%/2
428
429 Select from 0% to 10% time slice:
430
431 perf report --time 0%-10%
432
433 Select the first and second 10% time slices:
434
435 perf report --time 10%/1,10%/2
436
437 Select from 0% to 10% and 30% to 40% slices:
438
439 perf report --time 0%-10%,30%-40%
440
441--switch-on EVENT_NAME::
442 Only consider events after this event is found.
443
444 This may be interesting to measure a workload only after some initialization
445 phase is over, i.e. insert a perf probe at that point and then using this
446 option with that probe.
447
448--switch-off EVENT_NAME::
449 Stop considering events after this event is found.
450
451--show-on-off-events::
452 Show the --switch-on/off events too. This has no effect in 'perf report' now
453 but probably we'll make the default not to show the switch-on/off events
454 on the --group mode and if there is only one event besides the off/on ones,
455 go straight to the histogram browser, just like 'perf report' with no events
456 explicitely specified does.
457
458--itrace::
459 Options for decoding instruction tracing data. The options are:
460
461include::itrace.txt[]
462
463 To disable decoding entirely, use --no-itrace.
464
465--full-source-path::
466 Show the full path for source files for srcline output.
467
468--show-ref-call-graph::
469 When multiple events are sampled, it may not be needed to collect
470 callgraphs for all of them. The sample sites are usually nearby,
471 and it's enough to collect the callgraphs on a reference event.
472 So user can use "call-graph=no" event modifier to disable callgraph
473 for other events to reduce the overhead.
474 However, perf report cannot show callgraphs for the event which
475 disable the callgraph.
476 This option extends the perf report to show reference callgraphs,
477 which collected by reference event, in no callgraph event.
478
479--socket-filter::
480 Only report the samples on the processor socket that match with this filter
481
482--samples=N::
483 Save N individual samples for each histogram entry to show context in perf
484 report tui browser.
485
486--raw-trace::
487 When displaying traceevent output, do not use print fmt or plugins.
488
489--hierarchy::
490 Enable hierarchical output.
491
492--inline::
493 If a callgraph address belongs to an inlined function, the inline stack
494 will be printed. Each entry is function name or file/line. Enabled by
495 default, disable with --no-inline.
496
497--mmaps::
498 Show --tasks output plus mmap information in a format similar to
499 /proc/<PID>/maps.
500
501 Please note that not all mmaps are stored, options affecting which ones
502 are include 'perf record --data', for instance.
503
504--ns::
505 Show time stamps in nanoseconds.
506
507--stats::
508 Display overall events statistics without any further processing.
509 (like the one at the end of the perf report -D command)
510
511--tasks::
512 Display monitored tasks stored in perf data. Displaying pid/tid/ppid
513 plus the command string aligned to distinguish parent and child tasks.
514
515--percent-type::
516 Set annotation percent type from following choices:
517 global-period, local-period, global-hits, local-hits
518
519 The local/global keywords set if the percentage is computed
520 in the scope of the function (local) or the whole data (global).
521 The period/hits keywords set the base the percentage is computed
522 on - the samples period or the number of samples (hits).
523
524--time-quantum::
525 Configure time quantum for time sort key. Default 100ms.
526 Accepts s, us, ms, ns units.
527
528include::callchain-overhead-calculation.txt[]
529
530SEE ALSO
531--------
532linkperf:perf-stat[1], linkperf:perf-annotate[1], linkperf:perf-record[1]