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 $HOME/.perfconfig like this: 71 72# 73# This is the config file, and 74# a '#' and ';' character indicates a comment 75# 76 77 [colors] 78 # Color variables 79 top = red, default 80 medium = green, default 81 normal = lightgray, default 82 selected = white, lightgray 83 jump_arrows = blue, default 84 addr = magenta, default 85 root = white, blue 86 87 [tui] 88 # Defaults if linked with libslang 89 report = on 90 annotate = on 91 top = on 92 93 [buildid] 94 # Default, disable using /dev/null 95 dir = ~/.debug 96 97 [annotate] 98 # Defaults 99 hide_src_code = false 100 use_offset = true 101 jump_arrows = true 102 show_nr_jumps = false 103 104 [help] 105 # Format can be man, info, web or html 106 format = man 107 autocorrect = 0 108 109 [ui] 110 show-headers = true 111 112 [call-graph] 113 # fp (framepointer), dwarf 114 record-mode = fp 115 print-type = graph 116 order = caller 117 sort-key = function 118 119 [report] 120 # Defaults 121 sort_order = comm,dso,symbol 122 percent-limit = 0 123 queue-size = 0 124 children = true 125 group = true 126 skip-empty = true 127 128 129You can hide source code of annotate feature setting the config to false with 130 131 % perf config annotate.hide_src_code=true 132 133If you want to add or modify several config items, you can do like 134 135 % perf config ui.show-headers=false kmem.default=slab 136 137To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do 138 139 % perf config --user report.sort-order=srcline 140 141To change colors of selected line to other foreground and background colors 142in system config file (i.e. `$(sysconf)/perfconfig`), do 143 144 % perf config --system colors.selected=yellow,green 145 146To query the record mode of call graph, do 147 148 % perf config call-graph.record-mode 149 150If you want to know multiple config key/value pairs, you can do like 151 152 % perf config report.queue-size call-graph.order report.children 153 154To query the config value of sort order of call graph in user config file (i.e. `~/.perfconfig`), do 155 156 % perf config --user call-graph.sort-order 157 158To query the config value of buildid directory in system config file (i.e. `$(sysconf)/perfconfig`), do 159 160 % perf config --system buildid.dir 161 162Variables 163~~~~~~~~~ 164 165colors.*:: 166 The variables for customizing the colors used in the output for the 167 'report', 'top' and 'annotate' in the TUI. They should specify the 168 foreground and background colors, separated by a comma, for example: 169 170 medium = green, lightgray 171 172 If you want to use the color configured for you terminal, just leave it 173 as 'default', for example: 174 175 medium = default, lightgray 176 177 Available colors: 178 red, yellow, green, cyan, gray, black, blue, 179 white, default, magenta, lightgray 180 181 colors.top:: 182 'top' means a overhead percentage which is more than 5%. 183 And values of this variable specify percentage colors. 184 Basic key values are foreground-color 'red' and 185 background-color 'default'. 186 colors.medium:: 187 'medium' means a overhead percentage which has more than 0.5%. 188 Default values are 'green' and 'default'. 189 colors.normal:: 190 'normal' means the rest of overhead percentages 191 except 'top', 'medium', 'selected'. 192 Default values are 'lightgray' and 'default'. 193 colors.selected:: 194 This selects the colors for the current entry in a list of entries 195 from sub-commands (top, report, annotate). 196 Default values are 'black' and 'lightgray'. 197 colors.jump_arrows:: 198 Colors for jump arrows on assembly code listings 199 such as 'jns', 'jmp', 'jane', etc. 200 Default values are 'blue', 'default'. 201 colors.addr:: 202 This selects colors for addresses from 'annotate'. 203 Default values are 'magenta', 'default'. 204 colors.root:: 205 Colors for headers in the output of a sub-commands (top, report). 206 Default values are 'white', 'blue'. 207 208core.*:: 209 core.proc-map-timeout:: 210 Sets a timeout (in milliseconds) for parsing /proc/<pid>/maps files. 211 Can be overridden by the --proc-map-timeout option on supported 212 subcommands. The default timeout is 500ms. 213 214tui.*, gtk.*:: 215 Subcommands that can be configured here are 'top', 'report' and 'annotate'. 216 These values are booleans, for example: 217 218 [tui] 219 top = true 220 221 will make the TUI be the default for the 'top' subcommand. Those will be 222 available if the required libs were detected at tool build time. 223 224buildid.*:: 225 buildid.dir:: 226 Each executable and shared library in modern distributions comes with a 227 content based identifier that, if available, will be inserted in a 228 'perf.data' file header to, at analysis time find what is needed to do 229 symbol resolution, code annotation, etc. 230 231 The recording tools also stores a hard link or copy in a per-user 232 directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms 233 and /proc/kcore files to be used at analysis time. 234 235 The buildid.dir variable can be used to either change this directory 236 cache location, or to disable it altogether. If you want to disable it, 237 set buildid.dir to /dev/null. The default is $HOME/.debug 238 239buildid-cache.*:: 240 buildid-cache.debuginfod=URLs 241 Specify debuginfod URLs to be used when retrieving perf.data binaries, 242 it follows the same syntax as the DEBUGINFOD_URLS variable, like: 243 244 buildid-cache.debuginfod=http://192.168.122.174:8002 245 246annotate.*:: 247 These are in control of addresses, jump function, source code 248 in lines of assembly code from a specific program. 249 250 annotate.disassemblers:: 251 Choose the disassembler to use: "objdump", "llvm", "capstone", 252 if not specified it will first try, if available, the "llvm" one, 253 then, if it fails, "capstone", and finally the original "objdump" 254 based one. 255 256 Choosing a different one is useful when handling some feature that 257 is known to be best support at some point by one of the options, 258 to compare the output when in doubt about some bug, etc. 259 260 This can be a list, in order of preference, the first one that works 261 finishes the process. 262 263 annotate.addr2line:: 264 addr2line binary to use for file names and line numbers. 265 266 annotate.objdump:: 267 objdump binary to use for disassembly and annotations, 268 including in the 'perf test' command. 269 270 annotate.disassembler_style:: 271 Use this to change the default disassembler style to some other value 272 supported by binutils, such as "intel", see the '-M' option help in the 273 'objdump' man page. 274 275 annotate.hide_src_code:: 276 If a program which is analyzed has source code, 277 this option lets 'annotate' print a list of assembly code with the source code. 278 For example, let's see a part of a program. There're four lines. 279 If this option is 'true', they can be printed 280 without source code from a program as below. 281 282 │ push %rbp 283 │ mov %rsp,%rbp 284 │ sub $0x10,%rsp 285 │ mov (%rdi),%rdx 286 287 But if this option is 'false', source code of the part 288 can be also printed as below. Default is 'false'. 289 290 │ struct rb_node *rb_next(const struct rb_node *node) 291 │ { 292 │ push %rbp 293 │ mov %rsp,%rbp 294 │ sub $0x10,%rsp 295 │ struct rb_node *parent; 296 │ 297 │ if (RB_EMPTY_NODE(node)) 298 │ mov (%rdi),%rdx 299 │ return n; 300 301 This option works with tui, stdio2 browsers. 302 303 annotate.use_offset:: 304 Basing on a first address of a loaded function, offset can be used. 305 Instead of using original addresses of assembly code, 306 addresses subtracted from a base address can be printed. 307 Let's illustrate an example. 308 If a base address is 0XFFFFFFFF81624d50 as below, 309 310 ffffffff81624d50 <load0> 311 312 an address on assembly code has a specific absolute address as below 313 314 ffffffff816250b8:│ mov 0x8(%r14),%rdi 315 316 but if use_offset is 'true', an address subtracted from a base address is printed. 317 Default is true. This option is only applied to TUI. 318 319 368:│ mov 0x8(%r14),%rdi 320 321 This option works with tui, stdio2 browsers. 322 323 annotate.jump_arrows:: 324 There can be jump instruction among assembly code. 325 Depending on a boolean value of jump_arrows, 326 arrows can be printed or not which represent 327 where do the instruction jump into as below. 328 329 │ ┌──jmp 1333 330 │ │ xchg %ax,%ax 331 │1330:│ mov %r15,%r10 332 │1333:└─→cmp %r15,%r14 333 334 If jump_arrow is 'false', the arrows isn't printed as below. 335 Default is 'false'. 336 337 │ ↓ jmp 1333 338 │ xchg %ax,%ax 339 │1330: mov %r15,%r10 340 │1333: cmp %r15,%r14 341 342 This option works with tui browser. 343 344 annotate.show_linenr:: 345 When showing source code if this option is 'true', 346 line numbers are printed as below. 347 348 │1628 if (type & PERF_SAMPLE_IDENTIFIER) { 349 │ ↓ jne 508 350 │1628 data->id = *array; 351 │1629 array++; 352 │1630 } 353 354 However if this option is 'false', they aren't printed as below. 355 Default is 'false'. 356 357 │ if (type & PERF_SAMPLE_IDENTIFIER) { 358 │ ↓ jne 508 359 │ data->id = *array; 360 │ array++; 361 │ } 362 363 This option works with tui, stdio2 browsers. 364 365 annotate.show_nr_jumps:: 366 Let's see a part of assembly code. 367 368 │1382: movb $0x1,-0x270(%rbp) 369 370 If use this, the number of branches jumping to that address can be printed as below. 371 Default is 'false'. 372 373 │1 1382: movb $0x1,-0x270(%rbp) 374 375 This option works with tui, stdio2 browsers. 376 377 annotate.show_total_period:: 378 To compare two records on an instruction base, with this option 379 provided, display total number of samples that belong to a line 380 in assembly code. If this option is 'true', total periods are printed 381 instead of percent values as below. 382 383 302 │ mov %eax,%eax 384 385 But if this option is 'false', percent values for overhead are printed i.e. 386 Default is 'false'. 387 388 99.93 │ mov %eax,%eax 389 390 This option works with tui, stdio2, stdio browsers. 391 392 annotate.show_nr_samples:: 393 By default perf annotate shows percentage of samples. This option 394 can be used to print absolute number of samples. Ex, when set as 395 false: 396 397 Percent│ 398 74.03 │ mov %fs:0x28,%rax 399 400 When set as true: 401 402 Samples│ 403 6 │ mov %fs:0x28,%rax 404 405 This option works with tui, stdio2, stdio browsers. 406 407 annotate.offset_level:: 408 Default is '1', meaning just jump targets will have offsets show right beside 409 the instruction. When set to '2' 'call' instructions will also have its offsets 410 shown, 3 or higher will show offsets for all instructions. 411 412 This option works with tui, stdio2 browsers. 413 414 annotate.demangle:: 415 Demangle symbol names to human readable form. Default is 'true'. 416 417 annotate.demangle_kernel:: 418 Demangle kernel symbol names to human readable form. Default is 'true'. 419 420hist.*:: 421 hist.percentage:: 422 This option control the way to calculate overhead of filtered entries - 423 that means the value of this option is effective only if there's a 424 filter (by comm, dso or symbol name). Suppose a following example: 425 426 Overhead Symbols 427 ........ ....... 428 33.33% foo 429 33.33% bar 430 33.33% baz 431 432 This is an original overhead and we'll filter out the first 'foo' 433 entry. The value of 'relative' would increase the overhead of 'bar' 434 and 'baz' to 50.00% for each, while 'absolute' would show their 435 current overhead (33.33%). 436 437ui.*:: 438 ui.show-headers:: 439 This option controls display of column headers (like 'Overhead' and 'Symbol') 440 in 'report' and 'top'. If this option is false, they are hidden. 441 This option is only applied to TUI. 442 443call-graph.*:: 444 The following controls the handling of call-graphs (obtained via the 445 -g/--call-graph options). 446 447 call-graph.record-mode:: 448 The mode for user space can be 'fp' (frame pointer), 'dwarf' 449 and 'lbr'. The value 'dwarf' is effective only if libunwind 450 (or a recent version of libdw) is present on the system; 451 the value 'lbr' only works for certain cpus. The method for 452 kernel space is controlled not by this option but by the 453 kernel config (CONFIG_UNWINDER_*). 454 455 call-graph.dump-size:: 456 The size of stack to dump in order to do post-unwinding. Default is 8192 (byte). 457 When using dwarf into record-mode, the default size will be used if omitted. 458 459 call-graph.print-type:: 460 The print-types can be graph (graph absolute), fractal (graph relative), 461 flat and folded. This option controls a way to show overhead for each callchain 462 entry. Suppose a following example. 463 464 Overhead Symbols 465 ........ ....... 466 40.00% foo 467 | 468 ---foo 469 | 470 |--50.00%--bar 471 | main 472 | 473 --50.00%--baz 474 main 475 476 This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly 477 half and half so 'fractal' shows 50.00% for each 478 (meaning that it assumes 100% total overhead of 'foo'). 479 480 The 'graph' uses absolute overhead value of 'foo' as total so each of 481 'bar' and 'baz' callchain will have 20.00% of overhead. 482 If 'flat' is used, single column and linear exposure of call chains. 483 'folded' mean call chains are displayed in a line, separated by semicolons. 484 485 call-graph.order:: 486 This option controls print order of callchains. The default is 487 'callee' which means callee is printed at top and then followed by its 488 caller and so on. The 'caller' prints it in reverse order. 489 490 If this option is not set and report.children or top.children is 491 set to true (or the equivalent command line option is given), 492 the default value of this option is changed to 'caller' for the 493 execution of 'perf report' or 'perf top'. Other commands will 494 still default to 'callee'. 495 496 call-graph.sort-key:: 497 The callchains are merged if they contain same information. 498 The sort-key option determines a way to compare the callchains. 499 A value of 'sort-key' can be 'function' or 'address'. 500 The default is 'function'. 501 502 call-graph.threshold:: 503 When there're many callchains it'd print tons of lines. So perf omits 504 small callchains under a certain overhead (threshold) and this option 505 control the threshold. Default is 0.5 (%). The overhead is calculated 506 by value depends on call-graph.print-type. 507 508 call-graph.print-limit:: 509 This is a maximum number of lines of callchain printed for a single 510 histogram entry. Default is 0 which means no limitation. 511 512report.*:: 513 report.sort_order:: 514 Allows changing the default sort order from "comm,dso,symbol" to 515 some other default, for instance "sym,dso" may be more fitting for 516 kernel developers. 517 report.percent-limit:: 518 This one is mostly the same as call-graph.threshold but works for 519 histogram entries. Entries having an overhead lower than this 520 percentage will not be printed. Default is '0'. If percent-limit 521 is '10', only entries which have more than 10% of overhead will be 522 printed. 523 524 report.queue-size:: 525 This option sets up the maximum allocation size of the internal 526 event queue for ordering events. Default is 0, meaning no limit. 527 528 report.children:: 529 'Children' means functions called from another function. 530 If this option is true, 'perf report' cumulates callchains of children 531 and show (accumulated) total overhead as well as 'Self' overhead. 532 Please refer to the 'perf report' manual. The default is 'true'. 533 534 report.group:: 535 This option is to show event group information together. 536 Example output with this turned on, notice that there is one column 537 per event in the group, ref-cycles and cycles: 538 539 # group: {ref-cycles,cycles} 540 # ======== 541 # 542 # Samples: 7K of event 'anon group { ref-cycles, cycles }' 543 # Event count (approx.): 6876107743 544 # 545 # Overhead Command Shared Object Symbol 546 # ................ ....... ................. ................... 547 # 548 99.84% 99.76% noploop noploop [.] main 549 0.07% 0.00% noploop ld-2.15.so [.] strcmp 550 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del 551 552 report.skip-empty:: 553 This option can change default stat behavior with empty results. 554 If it's set true, 'perf report --stat' will not show 0 stats. 555 556top.*:: 557 top.children:: 558 Same as 'report.children'. So if it is enabled, the output of 'top' 559 command will have 'Children' overhead column as well as 'Self' overhead 560 column by default. 561 The default is 'true'. 562 563 top.call-graph:: 564 This is identical to 'call-graph.record-mode', except it is 565 applicable only for 'top' subcommand. This option ONLY setup 566 the unwind method. To enable 'perf top' to actually use it, 567 the command line option -g must be specified. 568 569man.*:: 570 man.viewer:: 571 This option can assign a tool to view manual pages when 'help' 572 subcommand was invoked. Supported tools are 'man', 'woman' 573 (with emacs client) and 'konqueror'. Default is 'man'. 574 575 New man viewer tool can be also added using 'man.<tool>.cmd' 576 or use different path using 'man.<tool>.path' config option. 577 578pager.*:: 579 pager.<subcommand>:: 580 When the subcommand is run on stdio, determine whether it uses 581 pager or not based on this value. Default is 'unspecified'. 582 583kmem.*:: 584 kmem.default:: 585 This option decides which allocator is to be analyzed if neither 586 '--slab' nor '--page' option is used. Default is 'slab'. 587 588record.*:: 589 record.build-id:: 590 This option can be 'cache', 'no-cache', 'skip' or 'mmap'. 591 'cache' is to post-process data and save/update the binaries into 592 the build-id cache (in ~/.debug). This is the default. 593 But if this option is 'no-cache', it will not update the build-id cache. 594 'skip' skips post-processing and does not update the cache. 595 'mmap' skips post-processing and reads build-ids from MMAP events. 596 597 record.call-graph:: 598 This is identical to 'call-graph.record-mode', except it is 599 applicable only for 'record' subcommand. This option ONLY setup 600 the unwind method. To enable 'perf record' to actually use it, 601 the command line option -g must be specified. 602 603 record.aio:: 604 Use 'n' control blocks in asynchronous (Posix AIO) trace writing 605 mode ('n' default: 1, max: 4). 606 607 record.debuginfod:: 608 Specify debuginfod URL to be used when cacheing perf.data binaries, 609 it follows the same syntax as the DEBUGINFOD_URLS variable, like: 610 611 http://192.168.122.174:8002 612 613 If the URLs is 'system', the value of DEBUGINFOD_URLS system environment 614 variable is used. 615 616diff.*:: 617 diff.order:: 618 This option sets the number of columns to sort the result. 619 The default is 0, which means sorting by baseline. 620 Setting it to 1 will sort the result by delta (or other 621 compute method selected). 622 623 diff.compute:: 624 This options sets the method for computing the diff result. 625 Possible values are 'delta', 'delta-abs', 'ratio' and 626 'wdiff'. Default is 'delta'. 627 628trace.*:: 629 trace.add_events:: 630 Allows adding a set of events to add to the ones specified 631 by the user, or use as a default one if none was specified. 632 The initial use case is to add augmented_raw_syscalls.o to 633 activate the 'perf trace' logic that looks for syscall 634 pointer contents after the normal tracepoint payload. 635 636 trace.args_alignment:: 637 Number of columns to align the argument list, default is 70, 638 use 40 for the strace default, zero to no alignment. 639 640 trace.no_inherit:: 641 Do not follow children threads. 642 643 trace.show_arg_names:: 644 Should syscall argument names be printed? If not then trace.show_zeros 645 will be set. 646 647 trace.show_duration:: 648 Show syscall duration. 649 650 trace.show_prefix:: 651 If set to 'yes' will show common string prefixes in tables. The default 652 is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED". 653 654 trace.show_timestamp:: 655 Show syscall start timestamp. 656 657 trace.show_zeros:: 658 Do not suppress syscall arguments that are equal to zero. 659 660 trace.tracepoint_beautifiers:: 661 Use "libtraceevent" to use that library to augment the tracepoint arguments, 662 "libbeauty", the default, to use the same argument beautifiers used in the 663 strace-like sys_enter+sys_exit lines. 664 665ftrace.*:: 666 ftrace.tracer:: 667 Can be used to select the default tracer when neither -G nor 668 -F option is not specified. Possible values are 'function' and 669 'function_graph'. 670 671samples.*:: 672 673 samples.context:: 674 Define how many ns worth of time to show 675 around samples in perf report sample context browser. 676 677scripts.*:: 678 679 Any option defines a script that is added to the scripts menu 680 in the interactive perf browser and whose output is displayed. 681 The name of the option is the name, the value is a script command line. 682 The script gets the same options passed as a full perf script, 683 in particular -i perfdata file, --cpu, --tid 684 685convert.*:: 686 687 convert.queue-size:: 688 Limit the size of ordered_events queue, so we could control 689 allocation size of perf data files without proper finished 690 round events. 691stat.*:: 692 693 stat.big-num:: 694 (boolean) Change the default for "--big-num". To make 695 "--no-big-num" the default, set "stat.big-num=false". 696 697intel-pt.*:: 698 699 intel-pt.cache-divisor:: 700 701 intel-pt.mispred-all:: 702 If set, Intel PT decoder will set the mispred flag on all 703 branches. 704 705 intel-pt.max-loops:: 706 If set and non-zero, the maximum number of unconditional 707 branches decoded without consuming any trace packets. If 708 the maximum is exceeded there will be a "Never-ending loop" 709 error. The default is 100000. 710 711auxtrace.*:: 712 713 auxtrace.dumpdir:: 714 s390 only. The directory to save the auxiliary trace buffer 715 can be changed using this option. Ex, auxtrace.dumpdir=/tmp. 716 If the directory does not exist or has the wrong file type, 717 the current directory is used. 718 719itrace.*:: 720 721 debug-log-buffer-size:: 722 Log size in bytes to output when using the option --itrace=d+e 723 Refer 'itrace' option of linkperf:perf-script[1] or 724 linkperf:perf-report[1]. The default is 16384. 725 726daemon.*:: 727 728 daemon.base:: 729 Base path for daemon data. All sessions data are stored under 730 this path. 731 732session-<NAME>.*:: 733 734 session-<NAME>.run:: 735 736 Defines new record session for daemon. The value is record's 737 command line without the 'record' keyword. 738 739SEE ALSO 740-------- 741linkperf:perf[1] 742