xref: /linux/tools/perf/Documentation/perf-report.txt (revision b4db9f840283caca0d904436f187ef56a9126eaa)
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 warnings or messages.  (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, addr.
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	- cgroup: cgroup pathname in the cgroupfs.
99	- transaction: Transaction abort flags.
100	- overhead: Overhead percentage of sample
101	- overhead_sys: Overhead percentage of sample running in system mode
102	- overhead_us: Overhead percentage of sample running in user mode
103	- overhead_guest_sys: Overhead percentage of sample running in system mode
104	on guest machine
105	- overhead_guest_us: Overhead percentage of sample running in user mode on
106	guest machine
107	- sample: Number of sample
108	- period: Raw number of event count of sample
109	- time: Separate the samples by time stamp with the resolution specified by
110	--time-quantum (default 100ms). Specify with overhead and before it.
111	- code_page_size: the code page size of sampled code address (ip)
112	- ins_lat: Instruction latency in core cycles. This is the global instruction
113	  latency
114	- local_ins_lat: Local instruction latency version
115	- p_stage_cyc: On powerpc, this presents the number of cycles spent in a
116	  pipeline stage. And currently supported only on powerpc.
117	- addr: (Full) virtual address of the sampled instruction
118	- retire_lat: On X86, this reports pipeline stall of this instruction compared
119	  to the previous instruction in cycles. And currently supported only on X86
120	- simd: Flags describing a SIMD operation. "e" for empty Arm SVE predicate. "p" for partial Arm SVE predicate
121	- type: Data type of sample memory access.
122	- typeoff: Offset in the data type of sample memory access.
123	- symoff: Offset in the symbol.
124
125	By default, comm, dso and symbol keys are used.
126	(i.e. --sort comm,dso,symbol)
127
128	If --branch-stack option is used, following sort keys are also
129	available:
130
131	- dso_from: name of library or module branched from
132	- dso_to: name of library or module branched to
133	- symbol_from: name of function branched from
134	- symbol_to: name of function branched to
135	- srcline_from: source file and line branched from
136	- srcline_to: source file and line branched to
137	- mispredict: "N" for predicted branch, "Y" for mispredicted branch
138	- in_tx: branch in TSX transaction
139	- abort: TSX transaction abort.
140	- cycles: Cycles in basic block
141
142	And default sort keys are changed to comm, dso_from, symbol_from, dso_to
143	and symbol_to, see '--branch-stack'.
144
145	When the sort key symbol is specified, columns "IPC" and "IPC Coverage"
146	are enabled automatically. Column "IPC" reports the average IPC per function
147	and column "IPC coverage" reports the percentage of instructions with
148	sampled IPC in this function. IPC means Instruction Per Cycle. If it's low,
149	it indicates there may be a performance bottleneck when the function is
150	executed, such as a memory access bottleneck. If a function has high overhead
151	and low IPC, it's worth further analyzing it to optimize its performance.
152
153	If the --mem-mode option is used, the following sort keys are also available
154	(incompatible with --branch-stack):
155	symbol_daddr, dso_daddr, locked, tlb, mem, snoop, dcacheline, blocked.
156
157	- symbol_daddr: name of data symbol being executed on at the time of sample
158	- dso_daddr: name of library or module containing the data being executed
159	on at the time of the sample
160	- locked: whether the bus was locked at the time of the sample
161	- tlb: type of tlb access for the data at the time of the sample
162	- mem: type of memory access for the data at the time of the sample
163	- snoop: type of snoop (if any) for the data at the time of the sample
164	- dcacheline: the cacheline the data address is on at the time of the sample
165	- phys_daddr: physical address of data being executed on at the time of sample
166	- data_page_size: the data page size of data being executed on at the time of sample
167	- blocked: reason of blocked load access for the data at the time of the sample
168
169	And the default sort keys are changed to local_weight, mem, sym, dso,
170	symbol_daddr, dso_daddr, snoop, tlb, locked, blocked, local_ins_lat,
171	see '--mem-mode'.
172
173	If the data file has tracepoint event(s), following (dynamic) sort keys
174	are also available:
175	trace, trace_fields, [<event>.]<field>[/raw]
176
177	- trace: pretty printed trace output in a single column
178	- trace_fields: fields in tracepoints in separate columns
179	- <field name>: optional event and field name for a specific field
180
181	The last form consists of event and field names.  If event name is
182	omitted, it searches all events for matching field name.  The matched
183	field will be shown only for the event has the field.  The event name
184	supports substring match so user doesn't need to specify full subsystem
185	and event name everytime.  For example, 'sched:sched_switch' event can
186	be shortened to 'switch' as long as it's not ambiguous.  Also event can
187	be specified by its index (starting from 1) preceded by the '%'.
188	So '%1' is the first event, '%2' is the second, and so on.
189
190	The field name can have '/raw' suffix which disables pretty printing
191	and shows raw field value like hex numbers.  The --raw-trace option
192	has the same effect for all dynamic sort keys.
193
194	The default sort keys are changed to 'trace' if all events in the data
195	file are tracepoint.
196
197-F::
198--fields=::
199	Specify output field - multiple keys can be specified in CSV format.
200	Following fields are available:
201	overhead, overhead_sys, overhead_us, overhead_children, sample and period.
202	Also it can contain any sort key(s).
203
204	By default, every sort keys not specified in -F will be appended
205	automatically.
206
207	If the keys starts with a prefix '+', then it will append the specified
208        field(s) to the default field order. For example: perf report -F +period,sample.
209
210-p::
211--parent=<regex>::
212        A regex filter to identify parent. The parent is a caller of this
213	function and searched through the callchain, thus it requires callchain
214	information recorded. The pattern is in the extended regex format and
215	defaults to "\^sys_|^do_page_fault", see '--sort parent'.
216
217-x::
218--exclude-other::
219        Only display entries with parent-match.
220
221-w::
222--column-widths=<width[,width...]>::
223	Force each column width to the provided list, for large terminal
224	readability.  0 means no limit (default behavior).
225
226-t::
227--field-separator=::
228	Use a special separator character and don't pad with spaces, replacing
229	all occurrences of this separator in symbol names (and other output)
230	with a '.' character, that thus it's the only non valid separator.
231
232-D::
233--dump-raw-trace::
234        Dump raw trace in ASCII.
235
236--disable-order::
237	Disable raw trace ordering.
238
239-g::
240--call-graph=<print_type,threshold[,print_limit],order,sort_key[,branch],value>::
241        Display call chains using type, min percent threshold, print limit,
242	call order, sort key, optional branch and value.  Note that ordering
243	is not fixed so any parameter can be given in an arbitrary order.
244	One exception is the print_limit which should be preceded by threshold.
245
246	print_type can be either:
247	- flat: single column, linear exposure of call chains.
248	- graph: use a graph tree, displaying absolute overhead rates. (default)
249	- fractal: like graph, but displays relative rates. Each branch of
250		 the tree is considered as a new profiled object.
251	- folded: call chains are displayed in a line, separated by semicolons
252	- none: disable call chain display.
253
254	threshold is a percentage value which specifies a minimum percent to be
255	included in the output call graph.  Default is 0.5 (%).
256
257	print_limit is only applied when stdio interface is used.  It's to limit
258	number of call graph entries in a single hist entry.  Note that it needs
259	to be given after threshold (but not necessarily consecutive).
260	Default is 0 (unlimited).
261
262	order can be either:
263	- callee: callee based call graph.
264	- caller: inverted caller based call graph.
265	Default is 'caller' when --children is used, otherwise 'callee'.
266
267	sort_key can be:
268	- function: compare on functions (default)
269	- address: compare on individual code addresses
270	- srcline: compare on source filename and line number
271
272	branch can be:
273	- branch: include last branch information in callgraph when available.
274	          Usually more convenient to use --branch-history for this.
275
276	value can be:
277	- percent: display overhead percent (default)
278	- period: display event period
279	- count: display event count
280
281--children::
282	Accumulate callchain of children to parent entry so that then can
283	show up in the output.  The output will have a new "Children" column
284	and will be sorted on the data.  It requires callchains are recorded.
285	See the `overhead calculation' section for more details. Enabled by
286	default, disable with --no-children.
287
288--max-stack::
289	Set the stack depth limit when parsing the callchain, anything
290	beyond the specified depth will be ignored. This is a trade-off
291	between information loss and faster processing especially for
292	workloads that can have a very long callchain stack.
293	Note that when using the --itrace option the synthesized callchain size
294	will override this value if the synthesized callchain size is bigger.
295
296	Default: 127
297
298-G::
299--inverted::
300        alias for inverted caller based call graph.
301
302--ignore-callees=<regex>::
303        Ignore callees of the function(s) matching the given regex.
304        This has the effect of collecting the callers of each such
305        function into one place in the call-graph tree.
306
307--pretty=<key>::
308        Pretty printing style.  key: normal, raw
309
310--stdio:: Use the stdio interface.
311
312--stdio-color::
313	'always', 'never' or 'auto', allowing configuring color output
314	via the command line, in addition to via "color.ui" .perfconfig.
315	Use '--stdio-color always' to generate color even when redirecting
316	to a pipe or file. Using just '--stdio-color' is equivalent to
317	using 'always'.
318
319--tui:: Use the TUI interface, that is integrated with annotate and allows
320        zooming into DSOs or threads, among other features. Use of --tui
321	requires a tty, if one is not present, as when piping to other
322	commands, the stdio interface is used.
323
324--gtk:: Use the GTK2 interface.
325
326-k::
327--vmlinux=<file>::
328        vmlinux pathname
329
330--ignore-vmlinux::
331	Ignore vmlinux files.
332
333--kallsyms=<file>::
334        kallsyms pathname
335
336-m::
337--modules::
338        Load module symbols. WARNING: This should only be used with -k and
339        a LIVE kernel.
340
341-f::
342--force::
343        Don't do ownership validation.
344
345--symfs=<directory>::
346        Look for files with symbols relative to this directory.
347
348-C::
349--cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
350	be provided as a comma-separated list with no space: 0,1. Ranges of
351	CPUs are specified with -: 0-2. Default is to report samples on all
352	CPUs.
353
354-M::
355--disassembler-style=:: Set disassembler style for objdump.
356
357--source::
358	Interleave source code with assembly code. Enabled by default,
359	disable with --no-source.
360
361--asm-raw::
362	Show raw instruction encoding of assembly instructions.
363
364--show-total-period:: Show a column with the sum of periods.
365
366-I::
367--show-info::
368	Display extended information about the perf.data file. This adds
369	information which may be very large and thus may clutter the display.
370	It currently includes: cpu and numa topology of the host system.
371
372-b::
373--branch-stack::
374	Use the addresses of sampled taken branches instead of the instruction
375	address to build the histograms. To generate meaningful output, the
376	perf.data file must have been obtained using perf record -b or
377	perf record --branch-filter xxx where xxx is a branch filter option.
378	perf report is able to auto-detect whether a perf.data file contains
379	branch stacks and it will automatically switch to the branch view mode,
380	unless --no-branch-stack is used.
381
382--branch-history::
383	Add the addresses of sampled taken branches to the callstack.
384	This allows to examine the path the program took to each sample.
385	The data collection must have used -b (or -j) and -g.
386
387--addr2line=<path>::
388        Path to addr2line binary.
389
390--objdump=<path>::
391        Path to objdump binary.
392
393--prefix=PREFIX::
394--prefix-strip=N::
395	Remove first N entries from source file path names in executables
396	and add PREFIX. This allows to display source code compiled on systems
397	with different file system layout.
398
399--group::
400	Show event group information together. It forces group output also
401	if there are no groups defined in data file.
402
403--group-sort-idx::
404	Sort the output by the event at the index n in group. If n is invalid,
405	sort by the first event. It can support multiple groups with different
406	amount of events. WARNING: This should be used on grouped events.
407
408--demangle::
409	Demangle symbol names to human readable form. It's enabled by default,
410	disable with --no-demangle.
411
412--demangle-kernel::
413	Demangle kernel symbol names to human readable form (for C++ kernels).
414
415--mem-mode::
416	Use the data addresses of samples in addition to instruction addresses
417	to build the histograms.  To generate meaningful output, the perf.data
418	file must have been obtained using perf record -d -W and using a
419	special event -e cpu/mem-loads/p or -e cpu/mem-stores/p. See
420	'perf mem' for simpler access.
421
422--percent-limit::
423	Do not show entries which have an overhead under that percent.
424	(Default: 0).  Note that this option also sets the percent limit (threshold)
425	of callchains.  However the default value of callchain threshold is
426	different than the default value of hist entries.  Please see the
427	--call-graph option for details.
428
429--percentage::
430	Determine how to display the overhead percentage of filtered entries.
431	Filters can be applied by --comms, --dsos and/or --symbols options and
432	Zoom operations on the TUI (thread, dso, etc).
433
434	"relative" means it's relative to filtered entries only so that the
435	sum of shown entries will be always 100%.  "absolute" means it retains
436	the original value before and after the filter is applied.
437
438--header::
439	Show header information in the perf.data file.  This includes
440	various information like hostname, OS and perf version, cpu/mem
441	info, perf command line, event list and so on.  Currently only
442	--stdio output supports this feature.
443
444--header-only::
445	Show only perf.data header (forces --stdio).
446
447--time::
448	Only analyze samples within given time window: <start>,<stop>. Times
449	have the format seconds.nanoseconds. If start is not given (i.e. time
450	string is ',x.y') then analysis starts at the beginning of the file. If
451	stop time is not given (i.e. time string is 'x.y,') then analysis goes
452	to end of file. Multiple ranges can be separated by spaces, which
453	requires the argument to be quoted e.g. --time "1234.567,1234.789 1235,"
454
455	Also support time percent with multiple time ranges. Time string is
456	'a%/n,b%/m,...' or 'a%-b%,c%-%d,...'.
457
458	For example:
459	Select the second 10% time slice:
460
461	  perf report --time 10%/2
462
463	Select from 0% to 10% time slice:
464
465	  perf report --time 0%-10%
466
467	Select the first and second 10% time slices:
468
469	  perf report --time 10%/1,10%/2
470
471	Select from 0% to 10% and 30% to 40% slices:
472
473	  perf report --time 0%-10%,30%-40%
474
475--switch-on EVENT_NAME::
476	Only consider events after this event is found.
477
478	This may be interesting to measure a workload only after some initialization
479	phase is over, i.e. insert a perf probe at that point and then using this
480	option with that probe.
481
482--switch-off EVENT_NAME::
483	Stop considering events after this event is found.
484
485--show-on-off-events::
486	Show the --switch-on/off events too. This has no effect in 'perf report' now
487	but probably we'll make the default not to show the switch-on/off events
488        on the --group mode and if there is only one event besides the off/on ones,
489	go straight to the histogram browser, just like 'perf report' with no events
490	explicitly specified does.
491
492--itrace::
493	Options for decoding instruction tracing data. The options are:
494
495include::itrace.txt[]
496
497	To disable decoding entirely, use --no-itrace.
498
499--full-source-path::
500	Show the full path for source files for srcline output.
501
502--show-ref-call-graph::
503	When multiple events are sampled, it may not be needed to collect
504	callgraphs for all of them. The sample sites are usually nearby,
505	and it's enough to collect the callgraphs on a reference event.
506	So user can use "call-graph=no" event modifier to disable callgraph
507	for other events to reduce the overhead.
508	However, perf report cannot show callgraphs for the event which
509	disable the callgraph.
510	This option extends the perf report to show reference callgraphs,
511	which collected by reference event, in no callgraph event.
512
513--stitch-lbr::
514	Show callgraph with stitched LBRs, which may have more complete
515	callgraph. The perf.data file must have been obtained using
516	perf record --call-graph lbr.
517	Disabled by default. In common cases with call stack overflows,
518	it can recreate better call stacks than the default lbr call stack
519	output. But this approach is not foolproof. There can be cases
520	where it creates incorrect call stacks from incorrect matches.
521	The known limitations include exception handing such as
522	setjmp/longjmp will have calls/returns not match.
523
524--socket-filter::
525	Only report the samples on the processor socket that match with this filter
526
527--samples=N::
528	Save N individual samples for each histogram entry to show context in perf
529	report tui browser.
530
531--raw-trace::
532	When displaying traceevent output, do not use print fmt or plugins.
533
534-H::
535--hierarchy::
536	Enable hierarchical output.  In the hierarchy mode, each sort key groups
537	samples based on the criteria and then sub-divide it using the lower
538	level sort key.
539
540	For example:
541	In normal output:
542
543	  perf report -s dso,sym
544	  # Overhead  Shared Object      Symbol
545	      50.00%  [kernel.kallsyms]  [k] kfunc1
546	      20.00%  perf               [.] foo
547	      15.00%  [kernel.kallsyms]  [k] kfunc2
548	      10.00%  perf               [.] bar
549	       5.00%  libc.so            [.] libcall
550
551	In hierarchy output:
552
553	  perf report -s dso,sym --hierarchy
554	  #   Overhead  Shared Object / Symbol
555	      65.00%    [kernel.kallsyms]
556	        50.00%    [k] kfunc1
557	        15.00%    [k] kfunc2
558	      30.00%    perf
559	        20.00%    [.] foo
560	        10.00%    [.] bar
561	       5.00%    libc.so
562	         5.00%    [.] libcall
563
564--inline::
565	If a callgraph address belongs to an inlined function, the inline stack
566	will be printed. Each entry is function name or file/line. Enabled by
567	default, disable with --no-inline.
568
569--mmaps::
570	Show --tasks output plus mmap information in a format similar to
571	/proc/<PID>/maps.
572
573	Please note that not all mmaps are stored, options affecting which ones
574	are include 'perf record --data', for instance.
575
576--ns::
577	Show time stamps in nanoseconds.
578
579--stats::
580	Display overall events statistics without any further processing.
581	(like the one at the end of the perf report -D command)
582
583--tasks::
584	Display monitored tasks stored in perf data. Displaying pid/tid/ppid
585	plus the command string aligned to distinguish parent and child tasks.
586
587--percent-type::
588	Set annotation percent type from following choices:
589	  global-period, local-period, global-hits, local-hits
590
591	The local/global keywords set if the percentage is computed
592	in the scope of the function (local) or the whole data (global).
593	The period/hits keywords set the base the percentage is computed
594	on - the samples period or the number of samples (hits).
595
596--time-quantum::
597	Configure time quantum for time sort key. Default 100ms.
598	Accepts s, us, ms, ns units.
599
600--total-cycles::
601	When --total-cycles is specified, it supports sorting for all blocks by
602	'Sampled Cycles%'. This is useful to concentrate on the globally hottest
603	blocks. In output, there are some new columns:
604
605	'Sampled Cycles%' - block sampled cycles aggregation / total sampled cycles
606	'Sampled Cycles'  - block sampled cycles aggregation
607	'Avg Cycles%'     - block average sampled cycles / sum of total block average
608			    sampled cycles
609	'Avg Cycles'      - block average sampled cycles
610
611--skip-empty::
612	Do not print 0 results in the --stat output.
613
614include::callchain-overhead-calculation.txt[]
615
616SEE ALSO
617--------
618linkperf:perf-stat[1], linkperf:perf-annotate[1], linkperf:perf-record[1],
619linkperf:perf-intel-pt[1]
620