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1perf-config(1)
2==============
3
4NAME
5----
6perf-config - Get and set variables in a configuration file.
7
8SYNOPSIS
9--------
10[verse]
11'perf config' [<file-option>] [section.name[=value] ...]
12or
13'perf config' [<file-option>] -l | --list
14
15DESCRIPTION
16-----------
17You can manage variables in a configuration file with this command.
18
19OPTIONS
20-------
21
22-l::
23--list::
24 Show current config variables, name and value, for all sections.
25
26--user::
27 For writing and reading options: write to user
28 '$HOME/.perfconfig' file or read it.
29
30--system::
31 For writing and reading options: write to system-wide
32 '$(sysconfdir)/perfconfig' or read it.
33
34CONFIGURATION FILE
35------------------
36
37The perf configuration file contains many variables to change various
38aspects of each of its tools, including output, disk usage, etc.
39The '$HOME/.perfconfig' file is used to store a per-user configuration.
40The file '$(sysconfdir)/perfconfig' can be used to
41store a system-wide default configuration.
42
43One an disable reading config files by setting the PERF_CONFIG environment
44variable to /dev/null, or provide an alternate config file by setting that
45variable.
46
47When reading or writing, the values are read from the system and user
48configuration files by default, and options '--system' and '--user'
49can be used to tell the command to read from or write to only that location.
50
51Syntax
52~~~~~~
53
54The file consist of sections. A section starts with its name
55surrounded by square brackets and continues till the next section
56begins. Each variable must be in a section, and have the form
57'name = value', for example:
58
59 [section]
60 name1 = value1
61 name2 = value2
62
63Section names are case sensitive and can contain any characters except
64newline (double quote `"` and backslash have to be escaped as `\"` and `\\`,
65respectively). Section headers can't span multiple lines.
66
67Example
68~~~~~~~
69
70Given a $HOME/.perfconfig like this:
71
72#
73# This is the config file, and
74# a '#' and ';' character indicates a comment
75#
76
77 [colors]
78 # Color variables
79 top = red, default
80 medium = green, default
81 normal = lightgray, default
82 selected = white, lightgray
83 jump_arrows = blue, default
84 addr = magenta, default
85 root = white, blue
86
87 [tui]
88 # Defaults if linked with libslang
89 report = on
90 annotate = on
91 top = on
92
93 [buildid]
94 # Default, disable using /dev/null
95 dir = ~/.debug
96
97 [annotate]
98 # Defaults
99 hide_src_code = false
100 use_offset = true
101 jump_arrows = true
102 show_nr_jumps = false
103
104 [help]
105 # Format can be man, info, web or html
106 format = man
107 autocorrect = 0
108
109 [ui]
110 show-headers = true
111
112 [call-graph]
113 # fp (framepointer), dwarf
114 record-mode = fp
115 print-type = graph
116 order = caller
117 sort-key = function
118
119 [report]
120 # Defaults
121 sort_order = comm,dso,symbol
122 percent-limit = 0
123 queue-size = 0
124 children = true
125 group = true
126 skip-empty = true
127
128 [llvm]
129 dump-obj = true
130 clang-opt = -g
131
132You can hide source code of annotate feature setting the config to false with
133
134 % perf config annotate.hide_src_code=true
135
136If you want to add or modify several config items, you can do like
137
138 % perf config ui.show-headers=false kmem.default=slab
139
140To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do
141
142 % perf config --user report.sort-order=srcline
143
144To change colors of selected line to other foreground and background colors
145in system config file (i.e. `$(sysconf)/perfconfig`), do
146
147 % perf config --system colors.selected=yellow,green
148
149To query the record mode of call graph, do
150
151 % perf config call-graph.record-mode
152
153If you want to know multiple config key/value pairs, you can do like
154
155 % perf config report.queue-size call-graph.order report.children
156
157To query the config value of sort order of call graph in user config file (i.e. `~/.perfconfig`), do
158
159 % perf config --user call-graph.sort-order
160
161To query the config value of buildid directory in system config file (i.e. `$(sysconf)/perfconfig`), do
162
163 % perf config --system buildid.dir
164
165Variables
166~~~~~~~~~
167
168colors.*::
169 The variables for customizing the colors used in the output for the
170 'report', 'top' and 'annotate' in the TUI. They should specify the
171 foreground and background colors, separated by a comma, for example:
172
173 medium = green, lightgray
174
175 If you want to use the color configured for you terminal, just leave it
176 as 'default', for example:
177
178 medium = default, lightgray
179
180 Available colors:
181 red, yellow, green, cyan, gray, black, blue,
182 white, default, magenta, lightgray
183
184 colors.top::
185 'top' means a overhead percentage which is more than 5%.
186 And values of this variable specify percentage colors.
187 Basic key values are foreground-color 'red' and
188 background-color 'default'.
189 colors.medium::
190 'medium' means a overhead percentage which has more than 0.5%.
191 Default values are 'green' and 'default'.
192 colors.normal::
193 'normal' means the rest of overhead percentages
194 except 'top', 'medium', 'selected'.
195 Default values are 'lightgray' and 'default'.
196 colors.selected::
197 This selects the colors for the current entry in a list of entries
198 from sub-commands (top, report, annotate).
199 Default values are 'black' and 'lightgray'.
200 colors.jump_arrows::
201 Colors for jump arrows on assembly code listings
202 such as 'jns', 'jmp', 'jane', etc.
203 Default values are 'blue', 'default'.
204 colors.addr::
205 This selects colors for addresses from 'annotate'.
206 Default values are 'magenta', 'default'.
207 colors.root::
208 Colors for headers in the output of a sub-commands (top, report).
209 Default values are 'white', 'blue'.
210
211core.*::
212 core.proc-map-timeout::
213 Sets a timeout (in milliseconds) for parsing /proc/<pid>/maps files.
214 Can be overridden by the --proc-map-timeout option on supported
215 subcommands. The default timeout is 500ms.
216
217tui.*, gtk.*::
218 Subcommands that can be configured here are 'top', 'report' and 'annotate'.
219 These values are booleans, for example:
220
221 [tui]
222 top = true
223
224 will make the TUI be the default for the 'top' subcommand. Those will be
225 available if the required libs were detected at tool build time.
226
227buildid.*::
228 buildid.dir::
229 Each executable and shared library in modern distributions comes with a
230 content based identifier that, if available, will be inserted in a
231 'perf.data' file header to, at analysis time find what is needed to do
232 symbol resolution, code annotation, etc.
233
234 The recording tools also stores a hard link or copy in a per-user
235 directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms
236 and /proc/kcore files to be used at analysis time.
237
238 The buildid.dir variable can be used to either change this directory
239 cache location, or to disable it altogether. If you want to disable it,
240 set buildid.dir to /dev/null. The default is $HOME/.debug
241
242buildid-cache.*::
243 buildid-cache.debuginfod=URLs
244 Specify debuginfod URLs to be used when retrieving perf.data binaries,
245 it follows the same syntax as the DEBUGINFOD_URLS variable, like:
246
247 buildid-cache.debuginfod=http://192.168.122.174:8002
248
249annotate.*::
250 These are in control of addresses, jump function, source code
251 in lines of assembly code from a specific program.
252
253 annotate.disassembler_style:
254 Use this to change the default disassembler style to some other value
255 supported by binutils, such as "intel", see the '-M' option help in the
256 'objdump' man page.
257
258 annotate.hide_src_code::
259 If a program which is analyzed has source code,
260 this option lets 'annotate' print a list of assembly code with the source code.
261 For example, let's see a part of a program. There're four lines.
262 If this option is 'true', they can be printed
263 without source code from a program as below.
264
265 │ push %rbp
266 │ mov %rsp,%rbp
267 │ sub $0x10,%rsp
268 │ mov (%rdi),%rdx
269
270 But if this option is 'false', source code of the part
271 can be also printed as below. Default is 'false'.
272
273 │ struct rb_node *rb_next(const struct rb_node *node)
274 │ {
275 │ push %rbp
276 │ mov %rsp,%rbp
277 │ sub $0x10,%rsp
278 │ struct rb_node *parent;
279 │
280 │ if (RB_EMPTY_NODE(node))
281 │ mov (%rdi),%rdx
282 │ return n;
283
284 This option works with tui, stdio2 browsers.
285
286 annotate.use_offset::
287 Basing on a first address of a loaded function, offset can be used.
288 Instead of using original addresses of assembly code,
289 addresses subtracted from a base address can be printed.
290 Let's illustrate an example.
291 If a base address is 0XFFFFFFFF81624d50 as below,
292
293 ffffffff81624d50 <load0>
294
295 an address on assembly code has a specific absolute address as below
296
297 ffffffff816250b8:│ mov 0x8(%r14),%rdi
298
299 but if use_offset is 'true', an address subtracted from a base address is printed.
300 Default is true. This option is only applied to TUI.
301
302 368:│ mov 0x8(%r14),%rdi
303
304 This option works with tui, stdio2 browsers.
305
306 annotate.jump_arrows::
307 There can be jump instruction among assembly code.
308 Depending on a boolean value of jump_arrows,
309 arrows can be printed or not which represent
310 where do the instruction jump into as below.
311
312 │ ┌──jmp 1333
313 │ │ xchg %ax,%ax
314 │1330:│ mov %r15,%r10
315 │1333:└─→cmp %r15,%r14
316
317 If jump_arrow is 'false', the arrows isn't printed as below.
318 Default is 'false'.
319
320 │ ↓ jmp 1333
321 │ xchg %ax,%ax
322 │1330: mov %r15,%r10
323 │1333: cmp %r15,%r14
324
325 This option works with tui browser.
326
327 annotate.show_linenr::
328 When showing source code if this option is 'true',
329 line numbers are printed as below.
330
331 │1628 if (type & PERF_SAMPLE_IDENTIFIER) {
332 │ ↓ jne 508
333 │1628 data->id = *array;
334 │1629 array++;
335 │1630 }
336
337 However if this option is 'false', they aren't printed as below.
338 Default is 'false'.
339
340 │ if (type & PERF_SAMPLE_IDENTIFIER) {
341 │ ↓ jne 508
342 │ data->id = *array;
343 │ array++;
344 │ }
345
346 This option works with tui, stdio2 browsers.
347
348 annotate.show_nr_jumps::
349 Let's see a part of assembly code.
350
351 │1382: movb $0x1,-0x270(%rbp)
352
353 If use this, the number of branches jumping to that address can be printed as below.
354 Default is 'false'.
355
356 │1 1382: movb $0x1,-0x270(%rbp)
357
358 This option works with tui, stdio2 browsers.
359
360 annotate.show_total_period::
361 To compare two records on an instruction base, with this option
362 provided, display total number of samples that belong to a line
363 in assembly code. If this option is 'true', total periods are printed
364 instead of percent values as below.
365
366 302 │ mov %eax,%eax
367
368 But if this option is 'false', percent values for overhead are printed i.e.
369 Default is 'false'.
370
371 99.93 │ mov %eax,%eax
372
373 This option works with tui, stdio2, stdio browsers.
374
375 annotate.show_nr_samples::
376 By default perf annotate shows percentage of samples. This option
377 can be used to print absolute number of samples. Ex, when set as
378 false:
379
380 Percent│
381 74.03 │ mov %fs:0x28,%rax
382
383 When set as true:
384
385 Samples│
386 6 │ mov %fs:0x28,%rax
387
388 This option works with tui, stdio2, stdio browsers.
389
390 annotate.offset_level::
391 Default is '1', meaning just jump targets will have offsets show right beside
392 the instruction. When set to '2' 'call' instructions will also have its offsets
393 shown, 3 or higher will show offsets for all instructions.
394
395 This option works with tui, stdio2 browsers.
396
397 annotate.demangle::
398 Demangle symbol names to human readable form. Default is 'true'.
399
400 annotate.demangle_kernel::
401 Demangle kernel symbol names to human readable form. Default is 'true'.
402
403hist.*::
404 hist.percentage::
405 This option control the way to calculate overhead of filtered entries -
406 that means the value of this option is effective only if there's a
407 filter (by comm, dso or symbol name). Suppose a following example:
408
409 Overhead Symbols
410 ........ .......
411 33.33% foo
412 33.33% bar
413 33.33% baz
414
415 This is an original overhead and we'll filter out the first 'foo'
416 entry. The value of 'relative' would increase the overhead of 'bar'
417 and 'baz' to 50.00% for each, while 'absolute' would show their
418 current overhead (33.33%).
419
420ui.*::
421 ui.show-headers::
422 This option controls display of column headers (like 'Overhead' and 'Symbol')
423 in 'report' and 'top'. If this option is false, they are hidden.
424 This option is only applied to TUI.
425
426call-graph.*::
427 The following controls the handling of call-graphs (obtained via the
428 -g/--call-graph options).
429
430 call-graph.record-mode::
431 The mode for user space can be 'fp' (frame pointer), 'dwarf'
432 and 'lbr'. The value 'dwarf' is effective only if libunwind
433 (or a recent version of libdw) is present on the system;
434 the value 'lbr' only works for certain cpus. The method for
435 kernel space is controlled not by this option but by the
436 kernel config (CONFIG_UNWINDER_*).
437
438 call-graph.dump-size::
439 The size of stack to dump in order to do post-unwinding. Default is 8192 (byte).
440 When using dwarf into record-mode, the default size will be used if omitted.
441
442 call-graph.print-type::
443 The print-types can be graph (graph absolute), fractal (graph relative),
444 flat and folded. This option controls a way to show overhead for each callchain
445 entry. Suppose a following example.
446
447 Overhead Symbols
448 ........ .......
449 40.00% foo
450 |
451 ---foo
452 |
453 |--50.00%--bar
454 | main
455 |
456 --50.00%--baz
457 main
458
459 This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly
460 half and half so 'fractal' shows 50.00% for each
461 (meaning that it assumes 100% total overhead of 'foo').
462
463 The 'graph' uses absolute overhead value of 'foo' as total so each of
464 'bar' and 'baz' callchain will have 20.00% of overhead.
465 If 'flat' is used, single column and linear exposure of call chains.
466 'folded' mean call chains are displayed in a line, separated by semicolons.
467
468 call-graph.order::
469 This option controls print order of callchains. The default is
470 'callee' which means callee is printed at top and then followed by its
471 caller and so on. The 'caller' prints it in reverse order.
472
473 If this option is not set and report.children or top.children is
474 set to true (or the equivalent command line option is given),
475 the default value of this option is changed to 'caller' for the
476 execution of 'perf report' or 'perf top'. Other commands will
477 still default to 'callee'.
478
479 call-graph.sort-key::
480 The callchains are merged if they contain same information.
481 The sort-key option determines a way to compare the callchains.
482 A value of 'sort-key' can be 'function' or 'address'.
483 The default is 'function'.
484
485 call-graph.threshold::
486 When there're many callchains it'd print tons of lines. So perf omits
487 small callchains under a certain overhead (threshold) and this option
488 control the threshold. Default is 0.5 (%). The overhead is calculated
489 by value depends on call-graph.print-type.
490
491 call-graph.print-limit::
492 This is a maximum number of lines of callchain printed for a single
493 histogram entry. Default is 0 which means no limitation.
494
495report.*::
496 report.sort_order::
497 Allows changing the default sort order from "comm,dso,symbol" to
498 some other default, for instance "sym,dso" may be more fitting for
499 kernel developers.
500 report.percent-limit::
501 This one is mostly the same as call-graph.threshold but works for
502 histogram entries. Entries having an overhead lower than this
503 percentage will not be printed. Default is '0'. If percent-limit
504 is '10', only entries which have more than 10% of overhead will be
505 printed.
506
507 report.queue-size::
508 This option sets up the maximum allocation size of the internal
509 event queue for ordering events. Default is 0, meaning no limit.
510
511 report.children::
512 'Children' means functions called from another function.
513 If this option is true, 'perf report' cumulates callchains of children
514 and show (accumulated) total overhead as well as 'Self' overhead.
515 Please refer to the 'perf report' manual. The default is 'true'.
516
517 report.group::
518 This option is to show event group information together.
519 Example output with this turned on, notice that there is one column
520 per event in the group, ref-cycles and cycles:
521
522 # group: {ref-cycles,cycles}
523 # ========
524 #
525 # Samples: 7K of event 'anon group { ref-cycles, cycles }'
526 # Event count (approx.): 6876107743
527 #
528 # Overhead Command Shared Object Symbol
529 # ................ ....... ................. ...................
530 #
531 99.84% 99.76% noploop noploop [.] main
532 0.07% 0.00% noploop ld-2.15.so [.] strcmp
533 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del
534
535 report.skip-empty::
536 This option can change default stat behavior with empty results.
537 If it's set true, 'perf report --stat' will not show 0 stats.
538
539top.*::
540 top.children::
541 Same as 'report.children'. So if it is enabled, the output of 'top'
542 command will have 'Children' overhead column as well as 'Self' overhead
543 column by default.
544 The default is 'true'.
545
546 top.call-graph::
547 This is identical to 'call-graph.record-mode', except it is
548 applicable only for 'top' subcommand. This option ONLY setup
549 the unwind method. To enable 'perf top' to actually use it,
550 the command line option -g must be specified.
551
552man.*::
553 man.viewer::
554 This option can assign a tool to view manual pages when 'help'
555 subcommand was invoked. Supported tools are 'man', 'woman'
556 (with emacs client) and 'konqueror'. Default is 'man'.
557
558 New man viewer tool can be also added using 'man.<tool>.cmd'
559 or use different path using 'man.<tool>.path' config option.
560
561pager.*::
562 pager.<subcommand>::
563 When the subcommand is run on stdio, determine whether it uses
564 pager or not based on this value. Default is 'unspecified'.
565
566kmem.*::
567 kmem.default::
568 This option decides which allocator is to be analyzed if neither
569 '--slab' nor '--page' option is used. Default is 'slab'.
570
571record.*::
572 record.build-id::
573 This option can be 'cache', 'no-cache', 'skip' or 'mmap'.
574 'cache' is to post-process data and save/update the binaries into
575 the build-id cache (in ~/.debug). This is the default.
576 But if this option is 'no-cache', it will not update the build-id cache.
577 'skip' skips post-processing and does not update the cache.
578 'mmap' skips post-processing and reads build-ids from MMAP events.
579
580 record.call-graph::
581 This is identical to 'call-graph.record-mode', except it is
582 applicable only for 'record' subcommand. This option ONLY setup
583 the unwind method. To enable 'perf record' to actually use it,
584 the command line option -g must be specified.
585
586 record.aio::
587 Use 'n' control blocks in asynchronous (Posix AIO) trace writing
588 mode ('n' default: 1, max: 4).
589
590 record.debuginfod::
591 Specify debuginfod URL to be used when cacheing perf.data binaries,
592 it follows the same syntax as the DEBUGINFOD_URLS variable, like:
593
594 http://192.168.122.174:8002
595
596 If the URLs is 'system', the value of DEBUGINFOD_URLS system environment
597 variable is used.
598
599diff.*::
600 diff.order::
601 This option sets the number of columns to sort the result.
602 The default is 0, which means sorting by baseline.
603 Setting it to 1 will sort the result by delta (or other
604 compute method selected).
605
606 diff.compute::
607 This options sets the method for computing the diff result.
608 Possible values are 'delta', 'delta-abs', 'ratio' and
609 'wdiff'. Default is 'delta'.
610
611trace.*::
612 trace.add_events::
613 Allows adding a set of events to add to the ones specified
614 by the user, or use as a default one if none was specified.
615 The initial use case is to add augmented_raw_syscalls.o to
616 activate the 'perf trace' logic that looks for syscall
617 pointer contents after the normal tracepoint payload.
618
619 trace.args_alignment::
620 Number of columns to align the argument list, default is 70,
621 use 40 for the strace default, zero to no alignment.
622
623 trace.no_inherit::
624 Do not follow children threads.
625
626 trace.show_arg_names::
627 Should syscall argument names be printed? If not then trace.show_zeros
628 will be set.
629
630 trace.show_duration::
631 Show syscall duration.
632
633 trace.show_prefix::
634 If set to 'yes' will show common string prefixes in tables. The default
635 is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED".
636
637 trace.show_timestamp::
638 Show syscall start timestamp.
639
640 trace.show_zeros::
641 Do not suppress syscall arguments that are equal to zero.
642
643 trace.tracepoint_beautifiers::
644 Use "libtraceevent" to use that library to augment the tracepoint arguments,
645 "libbeauty", the default, to use the same argument beautifiers used in the
646 strace-like sys_enter+sys_exit lines.
647
648ftrace.*::
649 ftrace.tracer::
650 Can be used to select the default tracer when neither -G nor
651 -F option is not specified. Possible values are 'function' and
652 'function_graph'.
653
654llvm.*::
655 llvm.clang-path::
656 Path to clang. If omit, search it from $PATH.
657
658 llvm.clang-bpf-cmd-template::
659 Cmdline template. Below lines show its default value. Environment
660 variable is used to pass options.
661 "$CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS "\
662 "-DLINUX_VERSION_CODE=$LINUX_VERSION_CODE " \
663 "$CLANG_OPTIONS $PERF_BPF_INC_OPTIONS $KERNEL_INC_OPTIONS " \
664 "-Wno-unused-value -Wno-pointer-sign " \
665 "-working-directory $WORKING_DIR " \
666 "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -O2 -o - $LLVM_OPTIONS_PIPE"
667
668 llvm.clang-opt::
669 Options passed to clang.
670
671 llvm.kbuild-dir::
672 kbuild directory. If not set, use /lib/modules/`uname -r`/build.
673 If set to "" deliberately, skip kernel header auto-detector.
674
675 llvm.kbuild-opts::
676 Options passed to 'make' when detecting kernel header options.
677
678 llvm.dump-obj::
679 Enable perf dump BPF object files compiled by LLVM.
680
681 llvm.opts::
682 Options passed to llc.
683
684samples.*::
685
686 samples.context::
687 Define how many ns worth of time to show
688 around samples in perf report sample context browser.
689
690scripts.*::
691
692 Any option defines a script that is added to the scripts menu
693 in the interactive perf browser and whose output is displayed.
694 The name of the option is the name, the value is a script command line.
695 The script gets the same options passed as a full perf script,
696 in particular -i perfdata file, --cpu, --tid
697
698convert.*::
699
700 convert.queue-size::
701 Limit the size of ordered_events queue, so we could control
702 allocation size of perf data files without proper finished
703 round events.
704stat.*::
705
706 stat.big-num::
707 (boolean) Change the default for "--big-num". To make
708 "--no-big-num" the default, set "stat.big-num=false".
709
710intel-pt.*::
711
712 intel-pt.cache-divisor::
713
714 intel-pt.mispred-all::
715 If set, Intel PT decoder will set the mispred flag on all
716 branches.
717
718 intel-pt.max-loops::
719 If set and non-zero, the maximum number of unconditional
720 branches decoded without consuming any trace packets. If
721 the maximum is exceeded there will be a "Never-ending loop"
722 error. The default is 100000.
723
724auxtrace.*::
725
726 auxtrace.dumpdir::
727 s390 only. The directory to save the auxiliary trace buffer
728 can be changed using this option. Ex, auxtrace.dumpdir=/tmp.
729 If the directory does not exist or has the wrong file type,
730 the current directory is used.
731
732itrace.*::
733
734 debug-log-buffer-size::
735 Log size in bytes to output when using the option --itrace=d+e
736 Refer 'itrace' option of linkperf:perf-script[1] or
737 linkperf:perf-report[1]. The default is 16384.
738
739daemon.*::
740
741 daemon.base::
742 Base path for daemon data. All sessions data are stored under
743 this path.
744
745session-<NAME>.*::
746
747 session-<NAME>.run::
748
749 Defines new record session for daemon. The value is record's
750 command line without the 'record' keyword.
751
752
753SEE ALSO
754--------
755linkperf:perf[1]
1perf-config(1)
2==============
3
4NAME
5----
6perf-config - Get and set variables in a configuration file.
7
8SYNOPSIS
9--------
10[verse]
11'perf config' [<file-option>] [section.name[=value] ...]
12or
13'perf config' [<file-option>] -l | --list
14
15DESCRIPTION
16-----------
17You can manage variables in a configuration file with this command.
18
19OPTIONS
20-------
21
22-l::
23--list::
24 Show current config variables, name and value, for all sections.
25
26--user::
27 For writing and reading options: write to user
28 '$HOME/.perfconfig' file or read it.
29
30--system::
31 For writing and reading options: write to system-wide
32 '$(sysconfdir)/perfconfig' or read it.
33
34CONFIGURATION FILE
35------------------
36
37The perf configuration file contains many variables to change various
38aspects of each of its tools, including output, disk usage, etc.
39The '$HOME/.perfconfig' file is used to store a per-user configuration.
40The file '$(sysconfdir)/perfconfig' can be used to
41store a system-wide default configuration.
42
43One an disable reading config files by setting the PERF_CONFIG environment
44variable to /dev/null, or provide an alternate config file by setting that
45variable.
46
47When reading or writing, the values are read from the system and user
48configuration files by default, and options '--system' and '--user'
49can be used to tell the command to read from or write to only that location.
50
51Syntax
52~~~~~~
53
54The file consist of sections. A section starts with its name
55surrounded by square brackets and continues till the next section
56begins. Each variable must be in a section, and have the form
57'name = value', for example:
58
59 [section]
60 name1 = value1
61 name2 = value2
62
63Section names are case sensitive and can contain any characters except
64newline (double quote `"` and backslash have to be escaped as `\"` and `\\`,
65respectively). Section headers can't span multiple lines.
66
67Example
68~~~~~~~
69
70Given a $HOME/.perfconfig like this:
71
72#
73# This is the config file, and
74# a '#' and ';' character indicates a comment
75#
76
77 [colors]
78 # Color variables
79 top = red, default
80 medium = green, default
81 normal = lightgray, default
82 selected = white, lightgray
83 jump_arrows = blue, default
84 addr = magenta, default
85 root = white, blue
86
87 [tui]
88 # Defaults if linked with libslang
89 report = on
90 annotate = on
91 top = on
92
93 [buildid]
94 # Default, disable using /dev/null
95 dir = ~/.debug
96
97 [annotate]
98 # Defaults
99 hide_src_code = false
100 use_offset = true
101 jump_arrows = true
102 show_nr_jumps = false
103
104 [help]
105 # Format can be man, info, web or html
106 format = man
107 autocorrect = 0
108
109 [ui]
110 show-headers = true
111
112 [call-graph]
113 # fp (framepointer), dwarf
114 record-mode = fp
115 print-type = graph
116 order = caller
117 sort-key = function
118
119 [report]
120 # Defaults
121 sort_order = comm,dso,symbol
122 percent-limit = 0
123 queue-size = 0
124 children = true
125 group = true
126
127 [llvm]
128 dump-obj = true
129 clang-opt = -g
130
131You can hide source code of annotate feature setting the config to false with
132
133 % perf config annotate.hide_src_code=true
134
135If you want to add or modify several config items, you can do like
136
137 % perf config ui.show-headers=false kmem.default=slab
138
139To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do
140
141 % perf config --user report sort-order=srcline
142
143To change colors of selected line to other foreground and background colors
144in system config file (i.e. `$(sysconf)/perfconfig`), do
145
146 % perf config --system colors.selected=yellow,green
147
148To query the record mode of call graph, do
149
150 % perf config call-graph.record-mode
151
152If you want to know multiple config key/value pairs, you can do like
153
154 % perf config report.queue-size call-graph.order report.children
155
156To query the config value of sort order of call graph in user config file (i.e. `~/.perfconfig`), do
157
158 % perf config --user call-graph.sort-order
159
160To query the config value of buildid directory in system config file (i.e. `$(sysconf)/perfconfig`), do
161
162 % perf config --system buildid.dir
163
164Variables
165~~~~~~~~~
166
167colors.*::
168 The variables for customizing the colors used in the output for the
169 'report', 'top' and 'annotate' in the TUI. They should specify the
170 foreground and background colors, separated by a comma, for example:
171
172 medium = green, lightgray
173
174 If you want to use the color configured for you terminal, just leave it
175 as 'default', for example:
176
177 medium = default, lightgray
178
179 Available colors:
180 red, yellow, green, cyan, gray, black, blue,
181 white, default, magenta, lightgray
182
183 colors.top::
184 'top' means a overhead percentage which is more than 5%.
185 And values of this variable specify percentage colors.
186 Basic key values are foreground-color 'red' and
187 background-color 'default'.
188 colors.medium::
189 'medium' means a overhead percentage which has more than 0.5%.
190 Default values are 'green' and 'default'.
191 colors.normal::
192 'normal' means the rest of overhead percentages
193 except 'top', 'medium', 'selected'.
194 Default values are 'lightgray' and 'default'.
195 colors.selected::
196 This selects the colors for the current entry in a list of entries
197 from sub-commands (top, report, annotate).
198 Default values are 'black' and 'lightgray'.
199 colors.jump_arrows::
200 Colors for jump arrows on assembly code listings
201 such as 'jns', 'jmp', 'jane', etc.
202 Default values are 'blue', 'default'.
203 colors.addr::
204 This selects colors for addresses from 'annotate'.
205 Default values are 'magenta', 'default'.
206 colors.root::
207 Colors for headers in the output of a sub-commands (top, report).
208 Default values are 'white', 'blue'.
209
210core.*::
211 core.proc-map-timeout::
212 Sets a timeout (in milliseconds) for parsing /proc/<pid>/maps files.
213 Can be overridden by the --proc-map-timeout option on supported
214 subcommands. The default timeout is 500ms.
215
216tui.*, gtk.*::
217 Subcommands that can be configured here are 'top', 'report' and 'annotate'.
218 These values are booleans, for example:
219
220 [tui]
221 top = true
222
223 will make the TUI be the default for the 'top' subcommand. Those will be
224 available if the required libs were detected at tool build time.
225
226buildid.*::
227 buildid.dir::
228 Each executable and shared library in modern distributions comes with a
229 content based identifier that, if available, will be inserted in a
230 'perf.data' file header to, at analysis time find what is needed to do
231 symbol resolution, code annotation, etc.
232
233 The recording tools also stores a hard link or copy in a per-user
234 directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms
235 and /proc/kcore files to be used at analysis time.
236
237 The buildid.dir variable can be used to either change this directory
238 cache location, or to disable it altogether. If you want to disable it,
239 set buildid.dir to /dev/null. The default is $HOME/.debug
240
241annotate.*::
242 These are in control of addresses, jump function, source code
243 in lines of assembly code from a specific program.
244
245 annotate.hide_src_code::
246 If a program which is analyzed has source code,
247 this option lets 'annotate' print a list of assembly code with the source code.
248 For example, let's see a part of a program. There're four lines.
249 If this option is 'true', they can be printed
250 without source code from a program as below.
251
252 │ push %rbp
253 │ mov %rsp,%rbp
254 │ sub $0x10,%rsp
255 │ mov (%rdi),%rdx
256
257 But if this option is 'false', source code of the part
258 can be also printed as below. Default is 'false'.
259
260 │ struct rb_node *rb_next(const struct rb_node *node)
261 │ {
262 │ push %rbp
263 │ mov %rsp,%rbp
264 │ sub $0x10,%rsp
265 │ struct rb_node *parent;
266 │
267 │ if (RB_EMPTY_NODE(node))
268 │ mov (%rdi),%rdx
269 │ return n;
270
271 This option works with tui, stdio2 browsers.
272
273 annotate.use_offset::
274 Basing on a first address of a loaded function, offset can be used.
275 Instead of using original addresses of assembly code,
276 addresses subtracted from a base address can be printed.
277 Let's illustrate an example.
278 If a base address is 0XFFFFFFFF81624d50 as below,
279
280 ffffffff81624d50 <load0>
281
282 an address on assembly code has a specific absolute address as below
283
284 ffffffff816250b8:│ mov 0x8(%r14),%rdi
285
286 but if use_offset is 'true', an address subtracted from a base address is printed.
287 Default is true. This option is only applied to TUI.
288
289 368:│ mov 0x8(%r14),%rdi
290
291 This option works with tui, stdio2 browsers.
292
293 annotate.jump_arrows::
294 There can be jump instruction among assembly code.
295 Depending on a boolean value of jump_arrows,
296 arrows can be printed or not which represent
297 where do the instruction jump into as below.
298
299 │ ┌──jmp 1333
300 │ │ xchg %ax,%ax
301 │1330:│ mov %r15,%r10
302 │1333:└─→cmp %r15,%r14
303
304 If jump_arrow is 'false', the arrows isn't printed as below.
305 Default is 'false'.
306
307 │ ↓ jmp 1333
308 │ xchg %ax,%ax
309 │1330: mov %r15,%r10
310 │1333: cmp %r15,%r14
311
312 This option works with tui browser.
313
314 annotate.show_linenr::
315 When showing source code if this option is 'true',
316 line numbers are printed as below.
317
318 │1628 if (type & PERF_SAMPLE_IDENTIFIER) {
319 │ ↓ jne 508
320 │1628 data->id = *array;
321 │1629 array++;
322 │1630 }
323
324 However if this option is 'false', they aren't printed as below.
325 Default is 'false'.
326
327 │ if (type & PERF_SAMPLE_IDENTIFIER) {
328 │ ↓ jne 508
329 │ data->id = *array;
330 │ array++;
331 │ }
332
333 This option works with tui, stdio2 browsers.
334
335 annotate.show_nr_jumps::
336 Let's see a part of assembly code.
337
338 │1382: movb $0x1,-0x270(%rbp)
339
340 If use this, the number of branches jumping to that address can be printed as below.
341 Default is 'false'.
342
343 │1 1382: movb $0x1,-0x270(%rbp)
344
345 This option works with tui, stdio2 browsers.
346
347 annotate.show_total_period::
348 To compare two records on an instruction base, with this option
349 provided, display total number of samples that belong to a line
350 in assembly code. If this option is 'true', total periods are printed
351 instead of percent values as below.
352
353 302 │ mov %eax,%eax
354
355 But if this option is 'false', percent values for overhead are printed i.e.
356 Default is 'false'.
357
358 99.93 │ mov %eax,%eax
359
360 This option works with tui, stdio2, stdio browsers.
361
362 annotate.show_nr_samples::
363 By default perf annotate shows percentage of samples. This option
364 can be used to print absolute number of samples. Ex, when set as
365 false:
366
367 Percent│
368 74.03 │ mov %fs:0x28,%rax
369
370 When set as true:
371
372 Samples│
373 6 │ mov %fs:0x28,%rax
374
375 This option works with tui, stdio2, stdio browsers.
376
377 annotate.offset_level::
378 Default is '1', meaning just jump targets will have offsets show right beside
379 the instruction. When set to '2' 'call' instructions will also have its offsets
380 shown, 3 or higher will show offsets for all instructions.
381
382 This option works with tui, stdio2 browsers.
383
384hist.*::
385 hist.percentage::
386 This option control the way to calculate overhead of filtered entries -
387 that means the value of this option is effective only if there's a
388 filter (by comm, dso or symbol name). Suppose a following example:
389
390 Overhead Symbols
391 ........ .......
392 33.33% foo
393 33.33% bar
394 33.33% baz
395
396 This is an original overhead and we'll filter out the first 'foo'
397 entry. The value of 'relative' would increase the overhead of 'bar'
398 and 'baz' to 50.00% for each, while 'absolute' would show their
399 current overhead (33.33%).
400
401ui.*::
402 ui.show-headers::
403 This option controls display of column headers (like 'Overhead' and 'Symbol')
404 in 'report' and 'top'. If this option is false, they are hidden.
405 This option is only applied to TUI.
406
407call-graph.*::
408 The following controls the handling of call-graphs (obtained via the
409 -g/--call-graph options).
410
411 call-graph.record-mode::
412 The mode for user space can be 'fp' (frame pointer), 'dwarf'
413 and 'lbr'. The value 'dwarf' is effective only if libunwind
414 (or a recent version of libdw) is present on the system;
415 the value 'lbr' only works for certain cpus. The method for
416 kernel space is controlled not by this option but by the
417 kernel config (CONFIG_UNWINDER_*).
418
419 call-graph.dump-size::
420 The size of stack to dump in order to do post-unwinding. Default is 8192 (byte).
421 When using dwarf into record-mode, the default size will be used if omitted.
422
423 call-graph.print-type::
424 The print-types can be graph (graph absolute), fractal (graph relative),
425 flat and folded. This option controls a way to show overhead for each callchain
426 entry. Suppose a following example.
427
428 Overhead Symbols
429 ........ .......
430 40.00% foo
431 |
432 ---foo
433 |
434 |--50.00%--bar
435 | main
436 |
437 --50.00%--baz
438 main
439
440 This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly
441 half and half so 'fractal' shows 50.00% for each
442 (meaning that it assumes 100% total overhead of 'foo').
443
444 The 'graph' uses absolute overhead value of 'foo' as total so each of
445 'bar' and 'baz' callchain will have 20.00% of overhead.
446 If 'flat' is used, single column and linear exposure of call chains.
447 'folded' mean call chains are displayed in a line, separated by semicolons.
448
449 call-graph.order::
450 This option controls print order of callchains. The default is
451 'callee' which means callee is printed at top and then followed by its
452 caller and so on. The 'caller' prints it in reverse order.
453
454 If this option is not set and report.children or top.children is
455 set to true (or the equivalent command line option is given),
456 the default value of this option is changed to 'caller' for the
457 execution of 'perf report' or 'perf top'. Other commands will
458 still default to 'callee'.
459
460 call-graph.sort-key::
461 The callchains are merged if they contain same information.
462 The sort-key option determines a way to compare the callchains.
463 A value of 'sort-key' can be 'function' or 'address'.
464 The default is 'function'.
465
466 call-graph.threshold::
467 When there're many callchains it'd print tons of lines. So perf omits
468 small callchains under a certain overhead (threshold) and this option
469 control the threshold. Default is 0.5 (%). The overhead is calculated
470 by value depends on call-graph.print-type.
471
472 call-graph.print-limit::
473 This is a maximum number of lines of callchain printed for a single
474 histogram entry. Default is 0 which means no limitation.
475
476report.*::
477 report.sort_order::
478 Allows changing the default sort order from "comm,dso,symbol" to
479 some other default, for instance "sym,dso" may be more fitting for
480 kernel developers.
481 report.percent-limit::
482 This one is mostly the same as call-graph.threshold but works for
483 histogram entries. Entries having an overhead lower than this
484 percentage will not be printed. Default is '0'. If percent-limit
485 is '10', only entries which have more than 10% of overhead will be
486 printed.
487
488 report.queue-size::
489 This option sets up the maximum allocation size of the internal
490 event queue for ordering events. Default is 0, meaning no limit.
491
492 report.children::
493 'Children' means functions called from another function.
494 If this option is true, 'perf report' cumulates callchains of children
495 and show (accumulated) total overhead as well as 'Self' overhead.
496 Please refer to the 'perf report' manual. The default is 'true'.
497
498 report.group::
499 This option is to show event group information together.
500 Example output with this turned on, notice that there is one column
501 per event in the group, ref-cycles and cycles:
502
503 # group: {ref-cycles,cycles}
504 # ========
505 #
506 # Samples: 7K of event 'anon group { ref-cycles, cycles }'
507 # Event count (approx.): 6876107743
508 #
509 # Overhead Command Shared Object Symbol
510 # ................ ....... ................. ...................
511 #
512 99.84% 99.76% noploop noploop [.] main
513 0.07% 0.00% noploop ld-2.15.so [.] strcmp
514 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del
515
516top.*::
517 top.children::
518 Same as 'report.children'. So if it is enabled, the output of 'top'
519 command will have 'Children' overhead column as well as 'Self' overhead
520 column by default.
521 The default is 'true'.
522
523 top.call-graph::
524 This is identical to 'call-graph.record-mode', except it is
525 applicable only for 'top' subcommand. This option ONLY setup
526 the unwind method. To enable 'perf top' to actually use it,
527 the command line option -g must be specified.
528
529man.*::
530 man.viewer::
531 This option can assign a tool to view manual pages when 'help'
532 subcommand was invoked. Supported tools are 'man', 'woman'
533 (with emacs client) and 'konqueror'. Default is 'man'.
534
535 New man viewer tool can be also added using 'man.<tool>.cmd'
536 or use different path using 'man.<tool>.path' config option.
537
538pager.*::
539 pager.<subcommand>::
540 When the subcommand is run on stdio, determine whether it uses
541 pager or not based on this value. Default is 'unspecified'.
542
543kmem.*::
544 kmem.default::
545 This option decides which allocator is to be analyzed if neither
546 '--slab' nor '--page' option is used. Default is 'slab'.
547
548record.*::
549 record.build-id::
550 This option can be 'cache', 'no-cache' or 'skip'.
551 'cache' is to post-process data and save/update the binaries into
552 the build-id cache (in ~/.debug). This is the default.
553 But if this option is 'no-cache', it will not update the build-id cache.
554 'skip' skips post-processing and does not update the cache.
555
556 record.call-graph::
557 This is identical to 'call-graph.record-mode', except it is
558 applicable only for 'record' subcommand. This option ONLY setup
559 the unwind method. To enable 'perf record' to actually use it,
560 the command line option -g must be specified.
561
562 record.aio::
563 Use 'n' control blocks in asynchronous (Posix AIO) trace writing
564 mode ('n' default: 1, max: 4).
565
566diff.*::
567 diff.order::
568 This option sets the number of columns to sort the result.
569 The default is 0, which means sorting by baseline.
570 Setting it to 1 will sort the result by delta (or other
571 compute method selected).
572
573 diff.compute::
574 This options sets the method for computing the diff result.
575 Possible values are 'delta', 'delta-abs', 'ratio' and
576 'wdiff'. Default is 'delta'.
577
578trace.*::
579 trace.add_events::
580 Allows adding a set of events to add to the ones specified
581 by the user, or use as a default one if none was specified.
582 The initial use case is to add augmented_raw_syscalls.o to
583 activate the 'perf trace' logic that looks for syscall
584 pointer contents after the normal tracepoint payload.
585
586 trace.args_alignment::
587 Number of columns to align the argument list, default is 70,
588 use 40 for the strace default, zero to no alignment.
589
590 trace.no_inherit::
591 Do not follow children threads.
592
593 trace.show_arg_names::
594 Should syscall argument names be printed? If not then trace.show_zeros
595 will be set.
596
597 trace.show_duration::
598 Show syscall duration.
599
600 trace.show_prefix::
601 If set to 'yes' will show common string prefixes in tables. The default
602 is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED".
603
604 trace.show_timestamp::
605 Show syscall start timestamp.
606
607 trace.show_zeros::
608 Do not suppress syscall arguments that are equal to zero.
609
610 trace.tracepoint_beautifiers::
611 Use "libtraceevent" to use that library to augment the tracepoint arguments,
612 "libbeauty", the default, to use the same argument beautifiers used in the
613 strace-like sys_enter+sys_exit lines.
614
615ftrace.*::
616 ftrace.tracer::
617 Can be used to select the default tracer when neither -G nor
618 -F option is not specified. Possible values are 'function' and
619 'function_graph'.
620
621llvm.*::
622 llvm.clang-path::
623 Path to clang. If omit, search it from $PATH.
624
625 llvm.clang-bpf-cmd-template::
626 Cmdline template. Below lines show its default value. Environment
627 variable is used to pass options.
628 "$CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS "\
629 "-DLINUX_VERSION_CODE=$LINUX_VERSION_CODE " \
630 "$CLANG_OPTIONS $PERF_BPF_INC_OPTIONS $KERNEL_INC_OPTIONS " \
631 "-Wno-unused-value -Wno-pointer-sign " \
632 "-working-directory $WORKING_DIR " \
633 "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -O2 -o - $LLVM_OPTIONS_PIPE"
634
635 llvm.clang-opt::
636 Options passed to clang.
637
638 llvm.kbuild-dir::
639 kbuild directory. If not set, use /lib/modules/`uname -r`/build.
640 If set to "" deliberately, skip kernel header auto-detector.
641
642 llvm.kbuild-opts::
643 Options passed to 'make' when detecting kernel header options.
644
645 llvm.dump-obj::
646 Enable perf dump BPF object files compiled by LLVM.
647
648 llvm.opts::
649 Options passed to llc.
650
651samples.*::
652
653 samples.context::
654 Define how many ns worth of time to show
655 around samples in perf report sample context browser.
656
657scripts.*::
658
659 Any option defines a script that is added to the scripts menu
660 in the interactive perf browser and whose output is displayed.
661 The name of the option is the name, the value is a script command line.
662 The script gets the same options passed as a full perf script,
663 in particular -i perfdata file, --cpu, --tid
664
665convert.*::
666
667 convert.queue-size::
668 Limit the size of ordered_events queue, so we could control
669 allocation size of perf data files without proper finished
670 round events.
671stat.*::
672
673 stat.big-num::
674 (boolean) Change the default for "--big-num". To make
675 "--no-big-num" the default, set "stat.big-num=false".
676
677intel-pt.*::
678
679 intel-pt.cache-divisor::
680
681 intel-pt.mispred-all::
682 If set, Intel PT decoder will set the mispred flag on all
683 branches.
684
685auxtrace.*::
686
687 auxtrace.dumpdir::
688 s390 only. The directory to save the auxiliary trace buffer
689 can be changed using this option. Ex, auxtrace.dumpdir=/tmp.
690 If the directory does not exist or has the wrong file type,
691 the current directory is used.
692
693SEE ALSO
694--------
695linkperf:perf[1]