summaryrefslogtreecommitdiffstats
path: root/tools/perf/Documentation/perf-top.txt
blob: 91d638df3a6bb9e6e9e8c10bb7ad3d2fc1e9efd0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
perf-top(1)
===========

NAME
----
perf-top - System profiling tool.

SYNOPSIS
--------
[verse]
'perf top' [-e <EVENT> | --event=EVENT] [<options>]

DESCRIPTION
-----------
This command generates and displays a performance counter profile in real time.


OPTIONS
-------
-a::
--all-cpus::
        System-wide collection.  (default)

-c <count>::
--count=<count>::
	Event period to sample.

-C <cpu-list>::
--cpu=<cpu>::
Monitor only on the list of CPUs provided. Multiple CPUs can be provided as a
comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2.
Default is to monitor all CPUS.

-d <seconds>::
--delay=<seconds>::
	Number of seconds to delay between refreshes.

-e <event>::
--event=<event>::
	Select the PMU event. Selection can be a symbolic event name
	(use 'perf list' to list all events) or a raw PMU
	event (eventsel+umask) in the form of rNNN where NNN is a
	hexadecimal event descriptor.

-E <entries>::
--entries=<entries>::
	Display this many functions.

-f <count>::
--count-filter=<count>::
	Only display functions with more events than this.

--group::
        Put the counters into a counter group.

-F <freq>::
--freq=<freq>::
	Profile at this frequency.

-i::
--inherit::
	Child tasks do not inherit counters.

-k <path>::
--vmlinux=<path>::
	Path to vmlinux.  Required for annotation functionality.

-m <pages>::
--mmap-pages=<pages>::
	Number of mmap data pages (must be a power of two) or size
	specification with appended unit character - B/K/M/G. The
	size is rounded up to have nearest pages power of two value.

-p <pid>::
--pid=<pid>::
	Profile events on existing Process ID (comma separated list).

-t <tid>::
--tid=<tid>::
        Profile events on existing thread ID (comma separated list).

-u::
--uid=::
        Record events in threads owned by uid. Name or number.

-r <priority>::
--realtime=<priority>::
	Collect data with this RT SCHED_FIFO priority.

--sym-annotate=<symbol>::
        Annotate this symbol.

-K::
--hide_kernel_symbols::
        Hide kernel symbols.

-U::
--hide_user_symbols::
        Hide user symbols.

--demangle-kernel::
        Demangle kernel symbols.

-D::
--dump-symtab::
        Dump the symbol table used for profiling.

-v::
--verbose::
	Be more verbose (show counter open errors, etc).

-z::
--zero::
	Zero history across display updates.

-s::
--sort::
	Sort by key(s): pid, comm, dso, symbol, parent, srcline, weight,
	local_weight, abort, in_tx, transaction, overhead, sample, period.
	Please see description of --sort in the perf-report man page.

--fields=::
	Specify output field - multiple keys can be specified in CSV format.
	Following fields are available:
	overhead, overhead_sys, overhead_us, overhead_children, sample and period.
	Also it can contain any sort key(s).

	By default, every sort keys not specified in --field will be appended
	automatically.

-n::
--show-nr-samples::
	Show a column with the number of samples.

--show-total-period::
	Show a column with the sum of periods.

--dsos::
	Only consider symbols in these dsos.  This option will affect the
	percentage of the overhead column.  See --percentage for more info.

--comms::
	Only consider symbols in these comms.  This option will affect the
	percentage of the overhead column.  See --percentage for more info.

--symbols::
	Only consider these symbols.  This option will affect the
	percentage of the overhead column.  See --percentage for more info.

-M::
--disassembler-style=:: Set disassembler style for objdump.

--source::
	Interleave source code with assembly code. Enabled by default,
	disable with --no-source.

--asm-raw::
	Show raw instruction encoding of assembly instructions.

-g::
	Enables call-graph (stack chain/backtrace) recording.

--call-graph [mode,type,min[,limit],order[,key][,branch]]::
	Setup and enable call-graph (stack chain/backtrace) recording,
	implies -g.  See `--call-graph` section in perf-record and
	perf-report man pages for details.

--children::
	Accumulate callchain of children to parent entry so that then can
	show up in the output.  The output will have a new "Children" column
	and will be sorted on the data.  It requires -g/--call-graph option
	enabled.  See the `overhead calculation' section for more details.

--max-stack::
	Set the stack depth limit when parsing the callchain, anything
	beyond the specified depth will be ignored. This is a trade-off
	between information loss and faster processing especially for
	workloads that can have a very long callchain stack.

	Default: /proc/sys/kernel/perf_event_max_stack when present, 127 otherwise.

--ignore-callees=<regex>::
        Ignore callees of the function(s) matching the given regex.
        This has the effect of collecting the callers of each such
        function into one place in the call-graph tree.

--percent-limit::
	Do not show entries which have an overhead under that percent.
	(Default: 0).

--percentage::
	Determine how to display the overhead percentage of filtered entries.
	Filters can be applied by --comms, --dsos and/or --symbols options and
	Zoom operations on the TUI (thread, dso, etc).

	"relative" means it's relative to filtered entries only so that the
	sum of shown entries will be always 100%. "absolute" means it retains
	the original value before and after the filter is applied.

-w::
--column-widths=<width[,width...]>::
	Force each column width to the provided list, for large terminal
	readability.  0 means no limit (default behavior).

--proc-map-timeout::
	When processing pre-existing threads /proc/XXX/mmap, it may take
	a long time, because the file may be huge. A time out is needed
	in such cases.
	This option sets the time out limit. The default value is 500 ms.


-b::
--branch-any::
	Enable taken branch stack sampling. Any type of taken branch may be sampled.
	This is a shortcut for --branch-filter any. See --branch-filter for more infos.

-j::
--branch-filter::
	Enable taken branch stack sampling. Each sample captures a series of consecutive
	taken branches. The number of branches captured with each sample depends on the
	underlying hardware, the type of branches of interest, and the executed code.
	It is possible to select the types of branches captured by enabling filters.
	For a full list of modifiers please see the perf record manpage.

	The option requires at least one branch type among any, any_call, any_ret, ind_call, cond.
	The privilege levels may be omitted, in which case, the privilege levels of the associated
	event are applied to the branch filter. Both kernel (k) and hypervisor (hv) privilege
	levels are subject to permissions.  When sampling on multiple events, branch stack sampling
	is enabled for all the sampling events. The sampled branch type is the same for all events.
	The various filters must be specified as a comma separated list: --branch-filter any_ret,u,k
	Note that this feature may not be available on all processors.

--raw-trace::
	When displaying traceevent output, do not use print fmt or plugins.

--hierarchy::
	Enable hierarchy output.

INTERACTIVE PROMPTING KEYS
--------------------------

[d]::
	Display refresh delay.

[e]::
	Number of entries to display.

[E]::
	Event to display when multiple counters are active.

[f]::
	Profile display filter (>= hit count).

[F]::
	Annotation display filter (>= % of total).

[s]::
	Annotate symbol.

[S]::
	Stop annotation, return to full profile display.

[z]::
	Toggle event count zeroing across display updates.

[qQ]::
	Quit.

Pressing any unmapped key displays a menu, and prompts for input.

include::callchain-overhead-calculation.txt[]

SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-list[1], linkperf:perf-report[1]