6 perf-script - Read perf.data (created by perf record) and display trace output
11 'perf script' [<options>]
12 'perf script' [<options>] record <script> [<record-options>] <command>
13 'perf script' [<options>] report <script> [script-args]
14 'perf script' [<options>] <script> <required-script-args> [<record-options>] <command>
15 'perf script' [<options>] <top-script> [script-args]
19 This command reads the input file and displays the trace recorded.
21 There are several variants of perf script:
23 'perf script' to see a detailed trace of the workload that was
26 You can also run a set of pre-canned scripts that aggregate and
27 summarize the raw trace data in various ways (the list of scripts is
28 available via 'perf script -l'). The following variants allow you to
29 record and run those scripts:
31 'perf script record <script> <command>' to record the events required
32 for 'perf script report'. <script> is the name displayed in the
33 output of 'perf script --list' i.e. the actual script name minus any
34 language extension. If <command> is not specified, the events are
35 recorded using the -a (system-wide) 'perf record' option.
37 'perf script report <script> [args]' to run and display the results
38 of <script>. <script> is the name displayed in the output of 'perf
39 script --list' i.e. the actual script name minus any language
40 extension. The perf.data output from a previous run of 'perf script
41 record <script>' is used and should be present for this command to
42 succeed. [args] refers to the (mainly optional) args expected by
45 'perf script <script> <required-script-args> <command>' to both
46 record the events required for <script> and to run the <script>
47 using 'live-mode' i.e. without writing anything to disk. <script>
48 is the name displayed in the output of 'perf script --list' i.e. the
49 actual script name minus any language extension. If <command> is
50 not specified, the events are recorded using the -a (system-wide)
51 'perf record' option. If <script> has any required args, they
52 should be specified before <command>. This mode doesn't allow for
53 optional script args to be specified; if optional script args are
54 desired, they can be specified using separate 'perf script record'
55 and 'perf script report' commands, with the stdout of the record step
56 piped to the stdin of the report script, using the '-o -' and '-i -'
57 options of the corresponding commands.
59 'perf script <top-script>' to both record the events required for
60 <top-script> and to run the <top-script> using 'live-mode'
61 i.e. without writing anything to disk. <top-script> is the name
62 displayed in the output of 'perf script --list' i.e. the actual
63 script name minus any language extension; a <top-script> is defined
64 as any script name ending with the string 'top'.
66 [<record-options>] can be passed to the record steps of 'perf script
67 record' and 'live-mode' variants; this isn't possible however for
68 <top-script> 'live-mode' or 'perf script report' variants.
70 See the 'SEE ALSO' section for links to language-specific
71 information on how to write and run your own trace scripts.
76 Any command you can specify in a shell.
80 Display verbose dump of the trace data.
82 --dump-unsorted-raw-trace=::
83 Same as --dump-raw-trace but not sorted in time order.
87 Show latency attributes (irqs/preemption disabled, etc).
91 Display a list of available trace scripts.
95 Process trace data with the given script ([lang]:script[.ext]).
96 If the string 'lang' is specified in place of a script name, a
97 list of supported languages will be displayed instead.
101 Generate perf-script.[ext] starter script for given language,
102 using current perf.data.
105 Filter sample events using the given shared object file.
106 Refer linkperf:perf-dlfilter[1]
109 Pass 'arg' as an argument to the dlfilter. --dlarg may be repeated
110 to add more arguments.
113 Display a list of available dlfilters. Use with option -v (must come
114 before option --list-dlfilters) to show long descriptions.
117 Force system-wide collection. Scripts run without a <command>
118 normally use -a by default, while scripts run with a <command>
119 normally don't - this option allows the latter to be run in
124 Input file name. (default: perf.data unless stdin is a fifo)
128 Do various checks like samples ordering and lost events.
132 Comma separated list of fields to print. Options are:
133 comm, tid, pid, time, cpu, event, trace, ip, sym, dso, dsoff, addr, symoff,
134 srcline, period, iregs, uregs, brstack, brstacksym, flags, bpf-output,
135 brstackinsn, brstackinsnlen, brstackdisasm, brstackoff, callindent, insn, disasm,
136 insnlen, synth, phys_addr, metric, misc, srccode, ipc, data_page_size,
137 code_page_size, ins_lat, machine_pid, vcpu, cgroup, retire_lat, brcntr,
139 Field list can be prepended with the type, trace, sw or hw,
140 to indicate to which event type the field list applies.
141 e.g., -F sw:comm,tid,time,ip,sym and -F trace:time,cpu,trace
143 perf script -F <fields>
147 perf script -F trace:<fields> -F sw:<fields> -F hw:<fields>
149 i.e., the specified fields apply to all event types if the type string
152 In addition to overriding fields, it is also possible to add or remove
153 fields from the defaults. For example
157 removes the cpu field and adds the insn field. Adding/removing fields
158 cannot be mixed with normal overriding.
160 The arguments are processed in the order received. A later usage can
161 reset a prior request. e.g.:
163 -F trace: -F comm,tid,time,ip,sym
165 The first -F suppresses trace events (field list is ""), but then the
166 second invocation sets the fields to comm,tid,time,ip,sym. In this case a
167 warning is given to the user:
169 "Overriding previous field request for all events."
171 Alternatively, consider the order:
173 -F comm,tid,time,ip,sym -F trace:
175 The first -F sets the fields for all events and the second -F
176 suppresses trace events. The user is given a warning message about
177 the override, and the result of the above is that only S/W and H/W
178 events are displayed with the given fields.
180 It's possible tp add/remove fields only for specific event type:
184 removes cpu and period from software events.
186 For the 'wildcard' option if a user selected field is invalid for an
187 event type, a message is displayed to the user that the option is
188 ignored for that type. For example:
190 $ perf script -F comm,tid,trace
191 'trace' not valid for hardware events. Ignoring.
192 'trace' not valid for software events. Ignoring.
194 Alternatively, if the type is given an invalid field is specified it
195 is an error. For example:
197 perf script -v -F sw:comm,tid,trace
198 'trace' not valid for software events.
200 At this point usage is displayed, and perf-script exits.
202 The flags field is synthesized and may have a value when Instruction
203 Trace decoding. The flags are "bcrosyiABExghDt" which stand for branch,
204 call, return, conditional, system, asynchronous, interrupt,
205 transaction abort, trace begin, trace end, in transaction, VM-Entry,
206 VM-Exit, interrupt disabled and interrupt disable toggle respectively.
207 Known combinations of flags are printed more nicely e.g.
208 "call" for "bc", "return" for "br", "jcc" for "bo", "jmp" for "b",
209 "int" for "bci", "iret" for "bri", "syscall" for "bcs", "sysret" for "brs",
210 "async" for "by", "hw int" for "bcyi", "tx abrt" for "bA", "tr strt" for "bB",
211 "tr end" for "bE", "vmentry" for "bcg", "vmexit" for "bch".
212 However the "x", "D" and "t" flags will be displayed separately in those
213 cases e.g. "jcc (xD)" for a condition branch within a transaction
214 with interrupts disabled. Note, interrupts becoming disabled is "t",
215 whereas interrupts becoming enabled is "Dt".
217 The callindent field is synthesized and may have a value when
218 Instruction Trace decoding. For calls and returns, it will display the
219 name of the symbol indented with spaces to reflect the stack depth.
221 When doing instruction trace decoding, insn, disasm and insnlen give the
222 instruction bytes, disassembled instructions (requires libcapstone support)
223 and the instruction length of the current instruction respectively.
225 The synth field is used by synthesized events which may be created when
226 Instruction Trace decoding.
228 The ipc (instructions per cycle) field is synthesized and may have a value when
229 Instruction Trace decoding.
231 The machine_pid and vcpu fields are derived from data resulting from using
232 perf inject to insert a perf.data file recorded inside a virtual machine into
233 a perf.data file recorded on the host at the same time.
235 The cgroup fields requires sample having the cgroup id which is saved
236 when "--all-cgroups" option is passed to 'perf record'.
238 Finally, a user may not set fields to none for all event types.
239 i.e., -F "" is not allowed.
241 The brstack output includes branch related information with raw addresses using the
242 /v/v/v/v/cycles syntax in the following order:
243 FROM: branch source instruction
244 TO : branch target instruction
245 M/P/-: M=branch target mispredicted or branch direction was mispredicted, P=target predicted or direction predicted, -=not supported
246 X/- : X=branch inside a transactional region, -=not in transaction region or not supported
247 A/- : A=TSX abort entry, -=not aborted region or not supported
250 The brstacksym is identical to brstack, except that the FROM and TO addresses are printed in a symbolic form if possible.
252 When brstackinsn is specified the full assembler sequences of branch sequences for each sample
253 is printed. This is the full execution path leading to the sample. This is only supported when the
254 sample was recorded with perf record -b or -j any.
256 Use brstackinsnlen to print the brstackinsn lenght. For example, you
257 can’t know the next sequential instruction after an unconditional branch unless
258 you calculate that based on its length.
260 brstackdisasm acts like brstackinsn, but will print disassembled instructions if
261 perf is built with the capstone library.
263 The brstackoff field will print an offset into a specific dso/binary.
265 With the metric option perf script can compute metrics for
266 sampling periods, similar to perf stat. This requires
267 specifying a group with multiple events defining metrics with the :S option
268 for perf record. perf will sample on the first event, and
269 print computed metrics for all the events in the group. Please note
270 that the metric computed is averaged over the whole sampling
271 period (since the last sample), not just for the sample point.
273 For sample events it's possible to display misc field with -F +misc option,
274 following letters are displayed for each bit:
276 PERF_RECORD_MISC_KERNEL K
277 PERF_RECORD_MISC_USER U
278 PERF_RECORD_MISC_HYPERVISOR H
279 PERF_RECORD_MISC_GUEST_KERNEL G
280 PERF_RECORD_MISC_GUEST_USER g
281 PERF_RECORD_MISC_MMAP_DATA* M
282 PERF_RECORD_MISC_COMM_EXEC E
283 PERF_RECORD_MISC_SWITCH_OUT S
284 PERF_RECORD_MISC_SWITCH_OUT_PREEMPT Sp
286 $ perf script -F +misc ...
287 sched-messaging 1414 K 28690.636582: 4590 cycles ...
288 sched-messaging 1407 U 28690.636600: 325620 cycles ...
289 sched-messaging 1414 K 28690.636608: 19473 cycles ...
290 misc field ___________/
299 --symfs=<directory>::
300 Look for files with symbols relative to this directory.
304 When printing symbols do not display call chain.
307 Stop display of callgraph at these symbols
310 --cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
311 be provided as a comma-separated list with no space: 0,1. Ranges of
312 CPUs are specified with -: 0-2. Default is to report samples on all
317 Only display events for these comms. CSV that understands
318 file://filename entries.
321 Only show events for given process ID (comma separated list).
324 Only show events for given thread ID (comma separated list).
328 Display extended information about the perf.data file. This adds
329 information which may be very large and thus may clutter the display.
330 It currently includes: cpu and numa topology of the host system.
331 It can only be used with the perf script report mode.
334 Try to resolve the path of [kernel.kallsyms]
337 Display task related events (e.g. FORK, COMM, EXIT).
340 Display mmap related events (e.g. MMAP, MMAP2).
342 --show-namespace-events
343 Display namespace events i.e. events of type PERF_RECORD_NAMESPACES.
346 Display context switch events i.e. events of type PERF_RECORD_SWITCH or
347 PERF_RECORD_SWITCH_CPU_WIDE.
350 Display lost events i.e. events of type PERF_RECORD_LOST.
353 Display finished round events i.e. events of type PERF_RECORD_FINISHED_ROUND.
356 Display bpf events i.e. events of type PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT.
359 Display cgroup events i.e. events of type PERF_RECORD_CGROUP.
361 --show-text-poke-events
362 Display text poke events i.e. events of type PERF_RECORD_TEXT_POKE and
366 Demangle symbol names to human readable form. It's enabled by default,
367 disable with --no-demangle.
370 Demangle kernel symbol names to human readable form (for C++ kernels).
373 Path to addr2line binary.
376 Show perf.data header.
379 Show only perf.data header.
382 Options for decoding instruction tracing data. The options are:
384 include::itrace.txt[]
386 To disable decoding entirely, use --no-itrace.
389 Show the full path for source files for srcline output.
392 Set the stack depth limit when parsing the callchain, anything
393 beyond the specified depth will be ignored. This is a trade-off
394 between information loss and faster processing especially for
395 workloads that can have a very long callchain stack.
396 Note that when using the --itrace option the synthesized callchain size
397 will override this value if the synthesized callchain size is bigger.
402 Use 9 decimal places when displaying time (i.e. show the nanoseconds)
406 Don't do ownership validation.
409 Only analyze samples within given time window: <start>,<stop>. Times
410 have the format seconds.nanoseconds. If start is not given (i.e. time
411 string is ',x.y') then analysis starts at the beginning of the file. If
412 stop time is not given (i.e. time string is 'x.y,') then analysis goes
413 to end of file. Multiple ranges can be separated by spaces, which
414 requires the argument to be quoted e.g. --time "1234.567,1234.789 1235,"
416 Also support time percent with multiple time ranges. Time string is
417 'a%/n,b%/m,...' or 'a%-b%,c%-%d,...'.
420 Select the second 10% time slice:
421 perf script --time 10%/2
423 Select from 0% to 10% time slice:
424 perf script --time 0%-10%
426 Select the first and second 10% time slices:
427 perf script --time 10%/1,10%/2
429 Select from 0% to 10% and 30% to 40% slices:
430 perf script --time 0%-10%,30%-40%
433 Set the maximum number of program blocks to print with brstackinsn for
437 Print time stamps relative to trace start.
440 Print time stamps relative to previous event.
443 Create per event files with a "perf.data.EVENT.dump" name instead of
444 printing to stdout, useful, for instance, for generating flamegraphs.
447 If a callgraph address belongs to an inlined function, the inline stack
448 will be printed. Each entry has function name and file/line. Enabled by
449 default, disable with --no-inline.
451 --insn-trace[=<raw|disasm>]::
452 Show instruction stream in bytes (raw) or disassembled (disasm)
453 for intel_pt traces. The default is 'raw'. To use xed, combine
454 'raw' with --xed to show disassembly done by xed.
457 Run xed disassembler on output. Requires installing the xed disassembler.
460 --symbols=symbol[,symbol...]::
461 Only consider the listed symbols. Symbols are typically a name
462 but they may also be hexadecimal address.
464 The hexadecimal address may be the start address of a symbol or
465 any other address to filter the trace records
467 For example, to select the symbol noploop or the address 0x4007a0:
468 perf script --symbols=noploop,0x4007a0
470 Support filtering trace records by symbol name, start address of
471 symbol, any hexadecimal address and address range.
473 The comparison order is:
475 1. symbol name comparison
476 2. symbol start address comparison.
477 3. any hexadecimal address comparison.
478 4. address range comparison (see --addr-range).
481 Use with -S or --symbols to list traced records within address range.
483 For example, to list the traced records within the address range
484 [0x4007a0, 0x0x4007a9]:
485 perf script -S 0x4007a0 --addr-range 10
488 Only consider symbols in these DSOs.
491 Show call stream for intel_pt traces. The CPUs are interleaved, but
492 can be filtered with -C.
495 Show call and return stream for intel_pt traces.
498 For itrace only show specified functions and their callees for
499 itrace. Multiple functions can be separated by comma.
501 --switch-on EVENT_NAME::
502 Only consider events after this event is found.
504 --switch-off EVENT_NAME::
505 Stop considering events after this event is found.
507 --show-on-off-events::
508 Show the --switch-on/off events too.
511 Show callgraph with stitched LBRs, which may have more complete
512 callgraph. The perf.data file must have been obtained using
513 perf record --call-graph lbr.
514 Disabled by default. In common cases with call stack overflows,
515 it can recreate better call stacks than the default lbr call stack
516 output. But this approach is not foolproof. There can be cases
517 where it creates incorrect call stacks from incorrect matches.
518 The known limitations include exception handing such as
519 setjmp/longjmp will have calls/returns not match.
521 :GMEXAMPLECMD: script
523 include::guest-files.txt[]
527 linkperf:perf-record[1], linkperf:perf-script-perl[1],
528 linkperf:perf-script-python[1], linkperf:perf-intel-pt[1],
529 linkperf:perf-dlfilter[1]