6 perf-report - Read perf.data (created by perf record) and display the profile
11 'perf report' [-i <file> | --input=file]
15 This command displays the performance counter profile information recorded
22 Input file name. (default: perf.data unless stdin is a fifo)
26 Be more verbose. (show symbol address, etc)
30 Do not show any message. (Suppress -v)
34 Show the number of samples for each symbol
36 --show-cpu-utilization::
37 Show sample percentage for different cpu modes.
41 Show per-thread event counters. The input data file should be recorded
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.
49 Only show events for given process ID (comma separated list).
52 Only show events for given thread ID (comma separated list).
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.
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.
65 Only show symbols that match (partially) with this filter.
69 Only display entries resolved to a symbol.
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.
78 Each key has following meaning:
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
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
104 - overhead_guest_us: Overhead percentage of sample running in user mode on
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.
111 By default, comm, dso and symbol keys are used.
112 (i.e. --sort comm,dso,symbol)
114 If --branch-stack option is used, following sort keys are also
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
128 And default sort keys are changed to comm, dso_from, symbol_from, dso_to
129 and symbol_to, see '--branch-stack'.
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.
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.
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
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'.
156 If the data file has tracepoint event(s), following (dynamic) sort keys
158 trace, trace_fields, [<event>.]<field>[/raw]
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
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.
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.
177 The default sort keys are changed to 'trace' if all events in the data
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).
187 By default, every sort keys not specified in -F will be appended
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.
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'.
202 Only display entries with parent-match.
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).
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.
217 Dump raw trace in ASCII.
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.
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.
234 threshold is a percentage value which specifies a minimum percent to be
235 included in the output call graph. Default is 0.5 (%).
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).
243 - callee: callee based call graph.
244 - caller: inverted caller based call graph.
245 Default is 'caller' when --children is used, otherwise 'callee'.
248 - function: compare on functions (default)
249 - address: compare on individual code addresses
250 - srcline: compare on source filename and line number
253 - branch: include last branch information in callgraph when available.
254 Usually more convenient to use --branch-history for this.
257 - percent: display overhead percent (default)
258 - period: display event period
259 - count: display event count
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.
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.
280 alias for inverted caller based call graph.
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.
288 Pretty printing style. key: normal, raw
290 --stdio:: Use the stdio interface.
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
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.
304 --gtk:: Use the GTK2 interface.
311 Ignore vmlinux files.
318 Load module symbols. WARNING: This should only be used with -k and
323 Don't do ownership validation.
325 --symfs=<directory>::
326 Look for files with symbols relative to this directory.
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
335 --disassembler-style=:: Set disassembler style for objdump.
338 Interleave source code with assembly code. Enabled by default,
339 disable with --no-source.
342 Show raw instruction encoding of assembly instructions.
344 --show-total-period:: Show a column with the sum of periods.
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.
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.
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.
368 Path to objdump binary.
371 Show event group information together. It forces group output also
372 if there are no groups defined in data file.
375 Demangle symbol names to human readable form. It's enabled by default,
376 disable with --no-demangle.
379 Demangle kernel symbol names to human readable form (for C++ kernels).
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.
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.
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).
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.
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.
411 Show only perf.data header (forces --stdio).
414 Only analyze samples within given time window: <start>,<stop>. Times
415 have the format seconds.microseconds. 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
420 Also support time percent with multiple time range. Time string is
421 'a%/n,b%/m,...' or 'a%-b%,c%-%d,...'.
424 Select the second 10% time slice:
426 perf report --time 10%/2
428 Select from 0% to 10% time slice:
430 perf report --time 0%-10%
432 Select the first and second 10% time slices:
434 perf report --time 10%/1,10%/2
436 Select from 0% to 10% and 30% to 40% slices:
438 perf report --time 0%-10%,30%-40%
441 Options for decoding instruction tracing data. The options are:
443 include::itrace.txt[]
445 To disable decoding entirely, use --no-itrace.
448 Show the full path for source files for srcline output.
450 --show-ref-call-graph::
451 When multiple events are sampled, it may not be needed to collect
452 callgraphs for all of them. The sample sites are usually nearby,
453 and it's enough to collect the callgraphs on a reference event.
454 So user can use "call-graph=no" event modifier to disable callgraph
455 for other events to reduce the overhead.
456 However, perf report cannot show callgraphs for the event which
457 disable the callgraph.
458 This option extends the perf report to show reference callgraphs,
459 which collected by reference event, in no callgraph event.
462 Only report the samples on the processor socket that match with this filter
465 Save N individual samples for each histogram entry to show context in perf
469 When displaying traceevent output, do not use print fmt or plugins.
472 Enable hierarchical output.
475 If a callgraph address belongs to an inlined function, the inline stack
476 will be printed. Each entry is function name or file/line. Enabled by
477 default, disable with --no-inline.
480 Show --tasks output plus mmap information in a format similar to
483 Please note that not all mmaps are stored, options affecting which ones
484 are include 'perf record --data', for instance.
487 Show time stamps in nanoseconds.
490 Display overall events statistics without any further processing.
491 (like the one at the end of the perf report -D command)
494 Display monitored tasks stored in perf data. Displaying pid/tid/ppid
495 plus the command string aligned to distinguish parent and child tasks.
498 Set annotation percent type from following choices:
499 global-period, local-period, global-hits, local-hits
501 The local/global keywords set if the percentage is computed
502 in the scope of the function (local) or the whole data (global).
503 The period/hits keywords set the base the percentage is computed
504 on - the samples period or the number of samples (hits).
507 Configure time quantum for time sort key. Default 100ms.
508 Accepts s, us, ms, ns units.
510 include::callchain-overhead-calculation.txt[]
514 linkperf:perf-stat[1], linkperf:perf-annotate[1], linkperf:perf-record[1]