| blob | 462b3cde067546dae83fdf7930621e6e67450974 |
1 perf-config(1)
2 ==============
4 NAME
5 ----
6 perf-config - Get and set variables in a configuration file.
8 SYNOPSIS
9 --------
10 [verse]
11 'perf config' [<file-option>] [section.name[=value] ...]
12 or
13 'perf config' [<file-option>] -l | --list
15 DESCRIPTION
16 -----------
17 You can manage variables in a configuration file with this command.
19 OPTIONS
20 -------
22 -l::
23 --list::
24 Show current config variables, name and value, for all sections.
26 --user::
27 For writing and reading options: write to user
28 '$HOME/.perfconfig' file or read it.
30 --system::
31 For writing and reading options: write to system-wide
32 '$(sysconfdir)/perfconfig' or read it.
34 CONFIGURATION FILE
35 ------------------
37 The perf configuration file contains many variables to change various
38 aspects of each of its tools, including output, disk usage, etc.
39 The '$HOME/.perfconfig' file is used to store a per-user configuration.
40 The file '$(sysconfdir)/perfconfig' can be used to
41 store a system-wide default configuration.
43 When reading or writing, the values are read from the system and user
44 configuration files by default, and options '--system' and '--user'
45 can be used to tell the command to read from or write to only that location.
47 Syntax
48 ~~~~~~
50 The file consist of sections. A section starts with its name
51 surrounded by square brackets and continues till the next section
52 begins. Each variable must be in a section, and have the form
53 'name = value', for example:
55 [section]
56 name1 = value1
57 name2 = value2
59 Section names are case sensitive and can contain any characters except
60 newline (double quote `"` and backslash have to be escaped as `\"` and `\\`,
61 respectively). Section headers can't span multiple lines.
63 Example
64 ~~~~~~~
66 Given a $HOME/.perfconfig like this:
68 #
69 # This is the config file, and
70 # a '#' and ';' character indicates a comment
71 #
73 [colors]
74 # Color variables
75 top = red, default
76 medium = green, default
77 normal = lightgray, default
78 selected = white, lightgray
79 jump_arrows = blue, default
80 addr = magenta, default
81 root = white, blue
83 [tui]
84 # Defaults if linked with libslang
85 report = on
86 annotate = on
87 top = on
89 [buildid]
90 # Default, disable using /dev/null
91 dir = ~/.debug
93 [annotate]
94 # Defaults
95 hide_src_code = false
96 use_offset = true
97 jump_arrows = true
98 show_nr_jumps = false
100 [help]
101 # Format can be man, info, web or html
102 format = man
103 autocorrect = 0
105 [ui]
106 show-headers = true
108 [call-graph]
109 # fp (framepointer), dwarf
110 record-mode = fp
111 print-type = graph
112 order = caller
113 sort-key = function
115 [report]
116 # Defaults
117 sort_order = comm,dso,symbol
118 percent-limit = 0
119 queue-size = 0
120 children = true
121 group = true
123 [llvm]
124 dump-obj = true
125 clang-opt = -g
127 You can hide source code of annotate feature setting the config to false with
129 % perf config annotate.hide_src_code=true
131 If you want to add or modify several config items, you can do like
133 % perf config ui.show-headers=false kmem.default=slab
135 To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do
137 % perf config --user report sort-order=srcline
139 To change colors of selected line to other foreground and background colors
140 in system config file (i.e. `$(sysconf)/perfconfig`), do
142 % perf config --system colors.selected=yellow,green
144 To query the record mode of call graph, do
146 % perf config call-graph.record-mode
148 If you want to know multiple config key/value pairs, you can do like
150 % perf config report.queue-size call-graph.order report.children
152 To query the config value of sort order of call graph in user config file (i.e. `~/.perfconfig`), do
154 % perf config --user call-graph.sort-order
156 To query the config value of buildid directory in system config file (i.e. `$(sysconf)/perfconfig`), do
158 % perf config --system buildid.dir
160 Variables
161 ~~~~~~~~~
163 colors.*::
164 The variables for customizing the colors used in the output for the
165 'report', 'top' and 'annotate' in the TUI. They should specify the
166 foreground and background colors, separated by a comma, for example:
168 medium = green, lightgray
170 If you want to use the color configured for you terminal, just leave it
171 as 'default', for example:
173 medium = default, lightgray
175 Available colors:
176 red, yellow, green, cyan, gray, black, blue,
177 white, default, magenta, lightgray
179 colors.top::
180 'top' means a overhead percentage which is more than 5%.
181 And values of this variable specify percentage colors.
182 Basic key values are foreground-color 'red' and
183 background-color 'default'.
184 colors.medium::
185 'medium' means a overhead percentage which has more than 0.5%.
186 Default values are 'green' and 'default'.
187 colors.normal::
188 'normal' means the rest of overhead percentages
189 except 'top', 'medium', 'selected'.
190 Default values are 'lightgray' and 'default'.
191 colors.selected::
192 This selects the colors for the current entry in a list of entries
193 from sub-commands (top, report, annotate).
194 Default values are 'black' and 'lightgray'.
195 colors.jump_arrows::
196 Colors for jump arrows on assembly code listings
197 such as 'jns', 'jmp', 'jane', etc.
198 Default values are 'blue', 'default'.
199 colors.addr::
200 This selects colors for addresses from 'annotate'.
201 Default values are 'magenta', 'default'.
202 colors.root::
203 Colors for headers in the output of a sub-commands (top, report).
204 Default values are 'white', 'blue'.
206 core.*::
207 core.proc-map-timeout::
208 Sets a timeout (in milliseconds) for parsing /proc/<pid>/maps files.
209 Can be overridden by the --proc-map-timeout option on supported
210 subcommands. The default timeout is 500ms.
212 tui.*, gtk.*::
213 Subcommands that can be configured here are 'top', 'report' and 'annotate'.
214 These values are booleans, for example:
216 [tui]
217 top = true
219 will make the TUI be the default for the 'top' subcommand. Those will be
220 available if the required libs were detected at tool build time.
222 buildid.*::
223 buildid.dir::
224 Each executable and shared library in modern distributions comes with a
225 content based identifier that, if available, will be inserted in a
226 'perf.data' file header to, at analysis time find what is needed to do
227 symbol resolution, code annotation, etc.
229 The recording tools also stores a hard link or copy in a per-user
230 directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms
231 and /proc/kcore files to be used at analysis time.
233 The buildid.dir variable can be used to either change this directory
234 cache location, or to disable it altogether. If you want to disable it,
235 set buildid.dir to /dev/null. The default is $HOME/.debug
237 annotate.*::
238 These options work only for TUI.
239 These are in control of addresses, jump function, source code
240 in lines of assembly code from a specific program.
242 annotate.hide_src_code::
243 If a program which is analyzed has source code,
244 this option lets 'annotate' print a list of assembly code with the source code.
245 For example, let's see a part of a program. There're four lines.
246 If this option is 'true', they can be printed
247 without source code from a program as below.
249 │ push %rbp
250 │ mov %rsp,%rbp
251 │ sub $0x10,%rsp
252 │ mov (%rdi),%rdx
254 But if this option is 'false', source code of the part
255 can be also printed as below. Default is 'false'.
257 │ struct rb_node *rb_next(const struct rb_node *node)
258 │ {
259 │ push %rbp
260 │ mov %rsp,%rbp
261 │ sub $0x10,%rsp
262 │ struct rb_node *parent;
263 │
264 │ if (RB_EMPTY_NODE(node))
265 │ mov (%rdi),%rdx
266 │ return n;
268 annotate.use_offset::
269 Basing on a first address of a loaded function, offset can be used.
270 Instead of using original addresses of assembly code,
271 addresses subtracted from a base address can be printed.
272 Let's illustrate an example.
273 If a base address is 0XFFFFFFFF81624d50 as below,
275 ffffffff81624d50 <load0>
277 an address on assembly code has a specific absolute address as below
279 ffffffff816250b8:│ mov 0x8(%r14),%rdi
281 but if use_offset is 'true', an address subtracted from a base address is printed.
282 Default is true. This option is only applied to TUI.
284 368:│ mov 0x8(%r14),%rdi
286 annotate.jump_arrows::
287 There can be jump instruction among assembly code.
288 Depending on a boolean value of jump_arrows,
289 arrows can be printed or not which represent
290 where do the instruction jump into as below.
292 │ ┌──jmp 1333
293 │ │ xchg %ax,%ax
294 │1330:│ mov %r15,%r10
295 │1333:└─→cmp %r15,%r14
297 If jump_arrow is 'false', the arrows isn't printed as below.
298 Default is 'false'.
300 │ ↓ jmp 1333
301 │ xchg %ax,%ax
302 │1330: mov %r15,%r10
303 │1333: cmp %r15,%r14
305 annotate.show_linenr::
306 When showing source code if this option is 'true',
307 line numbers are printed as below.
309 │1628 if (type & PERF_SAMPLE_IDENTIFIER) {
310 │ ↓ jne 508
311 │1628 data->id = *array;
312 │1629 array++;
313 │1630 }
315 However if this option is 'false', they aren't printed as below.
316 Default is 'false'.
318 │ if (type & PERF_SAMPLE_IDENTIFIER) {
319 │ ↓ jne 508
320 │ data->id = *array;
321 │ array++;
322 │ }
324 annotate.show_nr_jumps::
325 Let's see a part of assembly code.
327 │1382: movb $0x1,-0x270(%rbp)
329 If use this, the number of branches jumping to that address can be printed as below.
330 Default is 'false'.
332 │1 1382: movb $0x1,-0x270(%rbp)
334 annotate.show_total_period::
335 To compare two records on an instruction base, with this option
336 provided, display total number of samples that belong to a line
337 in assembly code. If this option is 'true', total periods are printed
338 instead of percent values as below.
340 302 │ mov %eax,%eax
342 But if this option is 'false', percent values for overhead are printed i.e.
343 Default is 'false'.
345 99.93 │ mov %eax,%eax
347 annotate.offset_level::
348 Default is '1', meaning just jump targets will have offsets show right beside
349 the instruction. When set to '2' 'call' instructions will also have its offsets
350 shown, 3 or higher will show offsets for all instructions.
352 hist.*::
353 hist.percentage::
354 This option control the way to calculate overhead of filtered entries -
355 that means the value of this option is effective only if there's a
356 filter (by comm, dso or symbol name). Suppose a following example:
358 Overhead Symbols
359 ........ .......
360 33.33% foo
361 33.33% bar
362 33.33% baz
364 This is an original overhead and we'll filter out the first 'foo'
365 entry. The value of 'relative' would increase the overhead of 'bar'
366 and 'baz' to 50.00% for each, while 'absolute' would show their
367 current overhead (33.33%).
369 ui.*::
370 ui.show-headers::
371 This option controls display of column headers (like 'Overhead' and 'Symbol')
372 in 'report' and 'top'. If this option is false, they are hidden.
373 This option is only applied to TUI.
375 call-graph.*::
376 When sub-commands 'top' and 'report' work with -g/—-children
377 there're options in control of call-graph.
379 call-graph.record-mode::
380 The record-mode can be 'fp' (frame pointer), 'dwarf' and 'lbr'.
381 The value of 'dwarf' is effective only if perf detect needed library
382 (libunwind or a recent version of libdw).
383 'lbr' only work for cpus that support it.
385 call-graph.dump-size::
386 The size of stack to dump in order to do post-unwinding. Default is 8192 (byte).
387 When using dwarf into record-mode, the default size will be used if omitted.
389 call-graph.print-type::
390 The print-types can be graph (graph absolute), fractal (graph relative),
391 flat and folded. This option controls a way to show overhead for each callchain
392 entry. Suppose a following example.
394 Overhead Symbols
395 ........ .......
396 40.00% foo
397 |
398 ---foo
399 |
400 |--50.00%--bar
401 | main
402 |
403 --50.00%--baz
404 main
406 This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly
407 half and half so 'fractal' shows 50.00% for each
408 (meaning that it assumes 100% total overhead of 'foo').
410 The 'graph' uses absolute overhead value of 'foo' as total so each of
411 'bar' and 'baz' callchain will have 20.00% of overhead.
412 If 'flat' is used, single column and linear exposure of call chains.
413 'folded' mean call chains are displayed in a line, separated by semicolons.
415 call-graph.order::
416 This option controls print order of callchains. The default is
417 'callee' which means callee is printed at top and then followed by its
418 caller and so on. The 'caller' prints it in reverse order.
420 If this option is not set and report.children or top.children is
421 set to true (or the equivalent command line option is given),
422 the default value of this option is changed to 'caller' for the
423 execution of 'perf report' or 'perf top'. Other commands will
424 still default to 'callee'.
426 call-graph.sort-key::
427 The callchains are merged if they contain same information.
428 The sort-key option determines a way to compare the callchains.
429 A value of 'sort-key' can be 'function' or 'address'.
430 The default is 'function'.
432 call-graph.threshold::
433 When there're many callchains it'd print tons of lines. So perf omits
434 small callchains under a certain overhead (threshold) and this option
435 control the threshold. Default is 0.5 (%). The overhead is calculated
436 by value depends on call-graph.print-type.
438 call-graph.print-limit::
439 This is a maximum number of lines of callchain printed for a single
440 histogram entry. Default is 0 which means no limitation.
442 report.*::
443 report.sort_order::
444 Allows changing the default sort order from "comm,dso,symbol" to
445 some other default, for instance "sym,dso" may be more fitting for
446 kernel developers.
447 report.percent-limit::
448 This one is mostly the same as call-graph.threshold but works for
449 histogram entries. Entries having an overhead lower than this
450 percentage will not be printed. Default is '0'. If percent-limit
451 is '10', only entries which have more than 10% of overhead will be
452 printed.
454 report.queue-size::
455 This option sets up the maximum allocation size of the internal
456 event queue for ordering events. Default is 0, meaning no limit.
458 report.children::
459 'Children' means functions called from another function.
460 If this option is true, 'perf report' cumulates callchains of children
461 and show (accumulated) total overhead as well as 'Self' overhead.
462 Please refer to the 'perf report' manual. The default is 'true'.
464 report.group::
465 This option is to show event group information together.
466 Example output with this turned on, notice that there is one column
467 per event in the group, ref-cycles and cycles:
469 # group: {ref-cycles,cycles}
470 # ========
471 #
472 # Samples: 7K of event 'anon group { ref-cycles, cycles }'
473 # Event count (approx.): 6876107743
474 #
475 # Overhead Command Shared Object Symbol
476 # ................ ....... ................. ...................
477 #
478 99.84% 99.76% noploop noploop [.] main
479 0.07% 0.00% noploop ld-2.15.so [.] strcmp
480 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del
482 top.*::
483 top.children::
484 Same as 'report.children'. So if it is enabled, the output of 'top'
485 command will have 'Children' overhead column as well as 'Self' overhead
486 column by default.
487 The default is 'true'.
489 man.*::
490 man.viewer::
491 This option can assign a tool to view manual pages when 'help'
492 subcommand was invoked. Supported tools are 'man', 'woman'
493 (with emacs client) and 'konqueror'. Default is 'man'.
495 New man viewer tool can be also added using 'man.<tool>.cmd'
496 or use different path using 'man.<tool>.path' config option.
498 pager.*::
499 pager.<subcommand>::
500 When the subcommand is run on stdio, determine whether it uses
501 pager or not based on this value. Default is 'unspecified'.
503 kmem.*::
504 kmem.default::
505 This option decides which allocator is to be analyzed if neither
506 '--slab' nor '--page' option is used. Default is 'slab'.
508 record.*::
509 record.build-id::
510 This option can be 'cache', 'no-cache' or 'skip'.
511 'cache' is to post-process data and save/update the binaries into
512 the build-id cache (in ~/.debug). This is the default.
513 But if this option is 'no-cache', it will not update the build-id cache.
514 'skip' skips post-processing and does not update the cache.
516 diff.*::
517 diff.order::
518 This option sets the number of columns to sort the result.
519 The default is 0, which means sorting by baseline.
520 Setting it to 1 will sort the result by delta (or other
521 compute method selected).
523 diff.compute::
524 This options sets the method for computing the diff result.
525 Possible values are 'delta', 'delta-abs', 'ratio' and
526 'wdiff'. Default is 'delta'.
528 trace.*::
529 trace.add_events::
530 Allows adding a set of events to add to the ones specified
531 by the user, or use as a default one if none was specified.
532 The initial use case is to add augmented_raw_syscalls.o to
533 activate the 'perf trace' logic that looks for syscall
534 pointer contents after the normal tracepoint payload.
536 trace.args_alignment::
537 Number of columns to align the argument list, default is 70,
538 use 40 for the strace default, zero to no alignment.
540 trace.no_inherit::
541 Do not follow children threads.
543 trace.show_arg_names::
544 Should syscall argument names be printed? If not then trace.show_zeros
545 will be set.
547 trace.show_duration::
548 Show syscall duration.
550 trace.show_prefix::
551 If set to 'yes' will show common string prefixes in tables. The default
552 is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED".
554 trace.show_timestamp::
555 Show syscall start timestamp.
557 trace.show_zeros::
558 Do not suppress syscall arguments that are equal to zero.
560 llvm.*::
561 llvm.clang-path::
562 Path to clang. If omit, search it from $PATH.
564 llvm.clang-bpf-cmd-template::
565 Cmdline template. Below lines show its default value. Environment
566 variable is used to pass options.
567 "$CLANG_EXEC -D__KERNEL__ $CLANG_OPTIONS $KERNEL_INC_OPTIONS \
568 -Wno-unused-value -Wno-pointer-sign -working-directory \
569 $WORKING_DIR -c $CLANG_SOURCE -target bpf -O2 -o -"
571 llvm.clang-opt::
572 Options passed to clang.
574 llvm.kbuild-dir::
575 kbuild directory. If not set, use /lib/modules/`uname -r`/build.
576 If set to "" deliberately, skip kernel header auto-detector.
578 llvm.kbuild-opts::
579 Options passed to 'make' when detecting kernel header options.
581 llvm.dump-obj::
582 Enable perf dump BPF object files compiled by LLVM.
584 llvm.opts::
585 Options passed to llc.
587 samples.*::
589 samples.context::
590 Define how many ns worth of time to show
591 around samples in perf report sample context browser.
593 scripts.*::
595 Any option defines a script that is added to the scripts menu
596 in the interactive perf browser and whose output is displayed.
597 The name of the option is the name, the value is a script command line.
598 The script gets the same options passed as a full perf script,
599 in particular -i perfdata file, --cpu, --tid
601 SEE ALSO
602 --------
603 linkperf:perf[1]