| blob | 76408d986aed765a890831d926b4be9084f91e97 |
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 One an disable reading config files by setting the PERF_CONFIG environment
44 variable to /dev/null, or provide an alternate config file by setting that
45 variable.
47 When reading or writing, the values are read from the system and user
48 configuration files by default, and options '--system' and '--user'
49 can be used to tell the command to read from or write to only that location.
51 Syntax
52 ~~~~~~
54 The file consist of sections. A section starts with its name
55 surrounded by square brackets and continues till the next section
56 begins. Each variable must be in a section, and have the form
57 'name = value', for example:
59 [section]
60 name1 = value1
61 name2 = value2
63 Section names are case sensitive and can contain any characters except
64 newline (double quote `"` and backslash have to be escaped as `\"` and `\\`,
65 respectively). Section headers can't span multiple lines.
67 Example
68 ~~~~~~~
70 Given a $HOME/.perfconfig like this:
72 #
73 # This is the config file, and
74 # a '#' and ';' character indicates a comment
75 #
77 [colors]
78 # Color variables
79 top = red, default
80 medium = green, default
81 normal = lightgray, default
82 selected = white, lightgray
83 jump_arrows = blue, default
84 addr = magenta, default
85 root = white, blue
87 [tui]
88 # Defaults if linked with libslang
89 report = on
90 annotate = on
91 top = on
93 [buildid]
94 # Default, disable using /dev/null
95 dir = ~/.debug
97 [annotate]
98 # Defaults
99 hide_src_code = false
100 use_offset = true
101 jump_arrows = true
102 show_nr_jumps = false
104 [help]
105 # Format can be man, info, web or html
106 format = man
107 autocorrect = 0
109 [ui]
110 show-headers = true
112 [call-graph]
113 # fp (framepointer), dwarf
114 record-mode = fp
115 print-type = graph
116 order = caller
117 sort-key = function
119 [report]
120 # Defaults
121 sort_order = comm,dso,symbol
122 percent-limit = 0
123 queue-size = 0
124 children = true
125 group = true
127 [llvm]
128 dump-obj = true
129 clang-opt = -g
131 You can hide source code of annotate feature setting the config to false with
133 % perf config annotate.hide_src_code=true
135 If you want to add or modify several config items, you can do like
137 % perf config ui.show-headers=false kmem.default=slab
139 To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do
141 % perf config --user report sort-order=srcline
143 To change colors of selected line to other foreground and background colors
144 in system config file (i.e. `$(sysconf)/perfconfig`), do
146 % perf config --system colors.selected=yellow,green
148 To query the record mode of call graph, do
150 % perf config call-graph.record-mode
152 If you want to know multiple config key/value pairs, you can do like
154 % perf config report.queue-size call-graph.order report.children
156 To query the config value of sort order of call graph in user config file (i.e. `~/.perfconfig`), do
158 % perf config --user call-graph.sort-order
160 To query the config value of buildid directory in system config file (i.e. `$(sysconf)/perfconfig`), do
162 % perf config --system buildid.dir
164 Variables
165 ~~~~~~~~~
167 colors.*::
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:
172 medium = green, lightgray
174 If you want to use the color configured for you terminal, just leave it
175 as 'default', for example:
177 medium = default, lightgray
179 Available colors:
180 red, yellow, green, cyan, gray, black, blue,
181 white, default, magenta, lightgray
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'.
210 core.*::
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.
216 tui.*, gtk.*::
217 Subcommands that can be configured here are 'top', 'report' and 'annotate'.
218 These values are booleans, for example:
220 [tui]
221 top = true
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.
226 buildid.*::
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.
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.
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
241 annotate.*::
242 These are in control of addresses, jump function, source code
243 in lines of assembly code from a specific program.
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.
252 │ push %rbp
253 │ mov %rsp,%rbp
254 │ sub $0x10,%rsp
255 │ mov (%rdi),%rdx
257 But if this option is 'false', source code of the part
258 can be also printed as below. Default is 'false'.
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;
271 This option works with tui, stdio2 browsers.
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,
280 ffffffff81624d50 <load0>
282 an address on assembly code has a specific absolute address as below
284 ffffffff816250b8:│ mov 0x8(%r14),%rdi
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.
289 368:│ mov 0x8(%r14),%rdi
291 This option works with tui, stdio2 browsers.
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.
299 │ ┌──jmp 1333
300 │ │ xchg %ax,%ax
301 │1330:│ mov %r15,%r10
302 │1333:└─→cmp %r15,%r14
304 If jump_arrow is 'false', the arrows isn't printed as below.
305 Default is 'false'.
307 │ ↓ jmp 1333
308 │ xchg %ax,%ax
309 │1330: mov %r15,%r10
310 │1333: cmp %r15,%r14
312 This option works with tui browser.
314 annotate.show_linenr::
315 When showing source code if this option is 'true',
316 line numbers are printed as below.
318 │1628 if (type & PERF_SAMPLE_IDENTIFIER) {
319 │ ↓ jne 508
320 │1628 data->id = *array;
321 │1629 array++;
322 │1630 }
324 However if this option is 'false', they aren't printed as below.
325 Default is 'false'.
327 │ if (type & PERF_SAMPLE_IDENTIFIER) {
328 │ ↓ jne 508
329 │ data->id = *array;
330 │ array++;
331 │ }
333 This option works with tui, stdio2 browsers.
335 annotate.show_nr_jumps::
336 Let's see a part of assembly code.
338 │1382: movb $0x1,-0x270(%rbp)
340 If use this, the number of branches jumping to that address can be printed as below.
341 Default is 'false'.
343 │1 1382: movb $0x1,-0x270(%rbp)
345 This option works with tui, stdio2 browsers.
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.
353 302 │ mov %eax,%eax
355 But if this option is 'false', percent values for overhead are printed i.e.
356 Default is 'false'.
358 99.93 │ mov %eax,%eax
360 This option works with tui, stdio2, stdio browsers.
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:
367 Percent│
368 74.03 │ mov %fs:0x28,%rax
370 When set as true:
372 Samples│
373 6 │ mov %fs:0x28,%rax
375 This option works with tui, stdio2, stdio browsers.
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.
382 This option works with tui, stdio2 browsers.
384 hist.*::
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:
390 Overhead Symbols
391 ........ .......
392 33.33% foo
393 33.33% bar
394 33.33% baz
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%).
401 ui.*::
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.
407 call-graph.*::
408 The following controls the handling of call-graphs (obtained via the
409 -g/--call-graph options).
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_*).
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.
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.
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
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').
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.
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.
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'.
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'.
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.
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.
476 report.*::
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.
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.
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'.
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:
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
516 top.*::
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'.
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.
529 man.*::
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'.
535 New man viewer tool can be also added using 'man.<tool>.cmd'
536 or use different path using 'man.<tool>.path' config option.
538 pager.*::
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'.
543 kmem.*::
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'.
548 record.*::
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.
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.
562 record.aio::
563 Use 'n' control blocks in asynchronous (Posix AIO) trace writing
564 mode ('n' default: 1, max: 4).
566 diff.*::
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).
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'.
578 trace.*::
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.
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.
590 trace.no_inherit::
591 Do not follow children threads.
593 trace.show_arg_names::
594 Should syscall argument names be printed? If not then trace.show_zeros
595 will be set.
597 trace.show_duration::
598 Show syscall duration.
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".
604 trace.show_timestamp::
605 Show syscall start timestamp.
607 trace.show_zeros::
608 Do not suppress syscall arguments that are equal to zero.
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.
615 ftrace.*::
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'.
621 llvm.*::
622 llvm.clang-path::
623 Path to clang. If omit, search it from $PATH.
625 llvm.clang-bpf-cmd-template::
626 Cmdline template. Below lines show its default value. Environment
627 variable is used to pass options.
628 "$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"
635 llvm.clang-opt::
636 Options passed to clang.
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.
642 llvm.kbuild-opts::
643 Options passed to 'make' when detecting kernel header options.
645 llvm.dump-obj::
646 Enable perf dump BPF object files compiled by LLVM.
648 llvm.opts::
649 Options passed to llc.
651 samples.*::
653 samples.context::
654 Define how many ns worth of time to show
655 around samples in perf report sample context browser.
657 scripts.*::
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
665 convert.*::
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.
671 stat.*::
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".
677 intel-pt.*::
679 intel-pt.cache-divisor::
681 intel-pt.mispred-all::
682 If set, Intel PT decoder will set the mispred flag on all
683 branches.
685 auxtrace.*::
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.
693 SEE ALSO
694 --------
695 linkperf:perf[1]