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 241buildid-cache.*:: 242 buildid-cache.debuginfod=URLs 243 Specify debuginfod URLs to be used when retrieving perf.data binaries, 244 it follows the same syntax as the DEBUGINFOD_URLS variable, like: 245 246 buildid-cache.debuginfod=http://192.168.122.174:8002 247 248annotate.*:: 249 These are in control of addresses, jump function, source code 250 in lines of assembly code from a specific program. 251 252 annotate.disassembler_style: 253 Use this to change the default disassembler style to some other value 254 supported by binutils, such as "intel", see the '-M' option help in the 255 'objdump' man page. 256 257 annotate.hide_src_code:: 258 If a program which is analyzed has source code, 259 this option lets 'annotate' print a list of assembly code with the source code. 260 For example, let's see a part of a program. There're four lines. 261 If this option is 'true', they can be printed 262 without source code from a program as below. 263 264 │ push %rbp 265 │ mov %rsp,%rbp 266 │ sub $0x10,%rsp 267 │ mov (%rdi),%rdx 268 269 But if this option is 'false', source code of the part 270 can be also printed as below. Default is 'false'. 271 272 │ struct rb_node *rb_next(const struct rb_node *node) 273 │ { 274 │ push %rbp 275 │ mov %rsp,%rbp 276 │ sub $0x10,%rsp 277 │ struct rb_node *parent; 278 │ 279 │ if (RB_EMPTY_NODE(node)) 280 │ mov (%rdi),%rdx 281 │ return n; 282 283 This option works with tui, stdio2 browsers. 284 285 annotate.use_offset:: 286 Basing on a first address of a loaded function, offset can be used. 287 Instead of using original addresses of assembly code, 288 addresses subtracted from a base address can be printed. 289 Let's illustrate an example. 290 If a base address is 0XFFFFFFFF81624d50 as below, 291 292 ffffffff81624d50 <load0> 293 294 an address on assembly code has a specific absolute address as below 295 296 ffffffff816250b8:│ mov 0x8(%r14),%rdi 297 298 but if use_offset is 'true', an address subtracted from a base address is printed. 299 Default is true. This option is only applied to TUI. 300 301 368:│ mov 0x8(%r14),%rdi 302 303 This option works with tui, stdio2 browsers. 304 305 annotate.jump_arrows:: 306 There can be jump instruction among assembly code. 307 Depending on a boolean value of jump_arrows, 308 arrows can be printed or not which represent 309 where do the instruction jump into as below. 310 311 │ ┌──jmp 1333 312 │ │ xchg %ax,%ax 313 │1330:│ mov %r15,%r10 314 │1333:└─→cmp %r15,%r14 315 316 If jump_arrow is 'false', the arrows isn't printed as below. 317 Default is 'false'. 318 319 │ ↓ jmp 1333 320 │ xchg %ax,%ax 321 │1330: mov %r15,%r10 322 │1333: cmp %r15,%r14 323 324 This option works with tui browser. 325 326 annotate.show_linenr:: 327 When showing source code if this option is 'true', 328 line numbers are printed as below. 329 330 │1628 if (type & PERF_SAMPLE_IDENTIFIER) { 331 │ ↓ jne 508 332 │1628 data->id = *array; 333 │1629 array++; 334 │1630 } 335 336 However if this option is 'false', they aren't printed as below. 337 Default is 'false'. 338 339 │ if (type & PERF_SAMPLE_IDENTIFIER) { 340 │ ↓ jne 508 341 │ data->id = *array; 342 │ array++; 343 │ } 344 345 This option works with tui, stdio2 browsers. 346 347 annotate.show_nr_jumps:: 348 Let's see a part of assembly code. 349 350 │1382: movb $0x1,-0x270(%rbp) 351 352 If use this, the number of branches jumping to that address can be printed as below. 353 Default is 'false'. 354 355 │1 1382: movb $0x1,-0x270(%rbp) 356 357 This option works with tui, stdio2 browsers. 358 359 annotate.show_total_period:: 360 To compare two records on an instruction base, with this option 361 provided, display total number of samples that belong to a line 362 in assembly code. If this option is 'true', total periods are printed 363 instead of percent values as below. 364 365 302 │ mov %eax,%eax 366 367 But if this option is 'false', percent values for overhead are printed i.e. 368 Default is 'false'. 369 370 99.93 │ mov %eax,%eax 371 372 This option works with tui, stdio2, stdio browsers. 373 374 annotate.show_nr_samples:: 375 By default perf annotate shows percentage of samples. This option 376 can be used to print absolute number of samples. Ex, when set as 377 false: 378 379 Percent│ 380 74.03 │ mov %fs:0x28,%rax 381 382 When set as true: 383 384 Samples│ 385 6 │ mov %fs:0x28,%rax 386 387 This option works with tui, stdio2, stdio browsers. 388 389 annotate.offset_level:: 390 Default is '1', meaning just jump targets will have offsets show right beside 391 the instruction. When set to '2' 'call' instructions will also have its offsets 392 shown, 3 or higher will show offsets for all instructions. 393 394 This option works with tui, stdio2 browsers. 395 396hist.*:: 397 hist.percentage:: 398 This option control the way to calculate overhead of filtered entries - 399 that means the value of this option is effective only if there's a 400 filter (by comm, dso or symbol name). Suppose a following example: 401 402 Overhead Symbols 403 ........ ....... 404 33.33% foo 405 33.33% bar 406 33.33% baz 407 408 This is an original overhead and we'll filter out the first 'foo' 409 entry. The value of 'relative' would increase the overhead of 'bar' 410 and 'baz' to 50.00% for each, while 'absolute' would show their 411 current overhead (33.33%). 412 413ui.*:: 414 ui.show-headers:: 415 This option controls display of column headers (like 'Overhead' and 'Symbol') 416 in 'report' and 'top'. If this option is false, they are hidden. 417 This option is only applied to TUI. 418 419call-graph.*:: 420 The following controls the handling of call-graphs (obtained via the 421 -g/--call-graph options). 422 423 call-graph.record-mode:: 424 The mode for user space can be 'fp' (frame pointer), 'dwarf' 425 and 'lbr'. The value 'dwarf' is effective only if libunwind 426 (or a recent version of libdw) is present on the system; 427 the value 'lbr' only works for certain cpus. The method for 428 kernel space is controlled not by this option but by the 429 kernel config (CONFIG_UNWINDER_*). 430 431 call-graph.dump-size:: 432 The size of stack to dump in order to do post-unwinding. Default is 8192 (byte). 433 When using dwarf into record-mode, the default size will be used if omitted. 434 435 call-graph.print-type:: 436 The print-types can be graph (graph absolute), fractal (graph relative), 437 flat and folded. This option controls a way to show overhead for each callchain 438 entry. Suppose a following example. 439 440 Overhead Symbols 441 ........ ....... 442 40.00% foo 443 | 444 ---foo 445 | 446 |--50.00%--bar 447 | main 448 | 449 --50.00%--baz 450 main 451 452 This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly 453 half and half so 'fractal' shows 50.00% for each 454 (meaning that it assumes 100% total overhead of 'foo'). 455 456 The 'graph' uses absolute overhead value of 'foo' as total so each of 457 'bar' and 'baz' callchain will have 20.00% of overhead. 458 If 'flat' is used, single column and linear exposure of call chains. 459 'folded' mean call chains are displayed in a line, separated by semicolons. 460 461 call-graph.order:: 462 This option controls print order of callchains. The default is 463 'callee' which means callee is printed at top and then followed by its 464 caller and so on. The 'caller' prints it in reverse order. 465 466 If this option is not set and report.children or top.children is 467 set to true (or the equivalent command line option is given), 468 the default value of this option is changed to 'caller' for the 469 execution of 'perf report' or 'perf top'. Other commands will 470 still default to 'callee'. 471 472 call-graph.sort-key:: 473 The callchains are merged if they contain same information. 474 The sort-key option determines a way to compare the callchains. 475 A value of 'sort-key' can be 'function' or 'address'. 476 The default is 'function'. 477 478 call-graph.threshold:: 479 When there're many callchains it'd print tons of lines. So perf omits 480 small callchains under a certain overhead (threshold) and this option 481 control the threshold. Default is 0.5 (%). The overhead is calculated 482 by value depends on call-graph.print-type. 483 484 call-graph.print-limit:: 485 This is a maximum number of lines of callchain printed for a single 486 histogram entry. Default is 0 which means no limitation. 487 488report.*:: 489 report.sort_order:: 490 Allows changing the default sort order from "comm,dso,symbol" to 491 some other default, for instance "sym,dso" may be more fitting for 492 kernel developers. 493 report.percent-limit:: 494 This one is mostly the same as call-graph.threshold but works for 495 histogram entries. Entries having an overhead lower than this 496 percentage will not be printed. Default is '0'. If percent-limit 497 is '10', only entries which have more than 10% of overhead will be 498 printed. 499 500 report.queue-size:: 501 This option sets up the maximum allocation size of the internal 502 event queue for ordering events. Default is 0, meaning no limit. 503 504 report.children:: 505 'Children' means functions called from another function. 506 If this option is true, 'perf report' cumulates callchains of children 507 and show (accumulated) total overhead as well as 'Self' overhead. 508 Please refer to the 'perf report' manual. The default is 'true'. 509 510 report.group:: 511 This option is to show event group information together. 512 Example output with this turned on, notice that there is one column 513 per event in the group, ref-cycles and cycles: 514 515 # group: {ref-cycles,cycles} 516 # ======== 517 # 518 # Samples: 7K of event 'anon group { ref-cycles, cycles }' 519 # Event count (approx.): 6876107743 520 # 521 # Overhead Command Shared Object Symbol 522 # ................ ....... ................. ................... 523 # 524 99.84% 99.76% noploop noploop [.] main 525 0.07% 0.00% noploop ld-2.15.so [.] strcmp 526 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del 527 528top.*:: 529 top.children:: 530 Same as 'report.children'. So if it is enabled, the output of 'top' 531 command will have 'Children' overhead column as well as 'Self' overhead 532 column by default. 533 The default is 'true'. 534 535 top.call-graph:: 536 This is identical to 'call-graph.record-mode', except it is 537 applicable only for 'top' subcommand. This option ONLY setup 538 the unwind method. To enable 'perf top' to actually use it, 539 the command line option -g must be specified. 540 541man.*:: 542 man.viewer:: 543 This option can assign a tool to view manual pages when 'help' 544 subcommand was invoked. Supported tools are 'man', 'woman' 545 (with emacs client) and 'konqueror'. Default is 'man'. 546 547 New man viewer tool can be also added using 'man.<tool>.cmd' 548 or use different path using 'man.<tool>.path' config option. 549 550pager.*:: 551 pager.<subcommand>:: 552 When the subcommand is run on stdio, determine whether it uses 553 pager or not based on this value. Default is 'unspecified'. 554 555kmem.*:: 556 kmem.default:: 557 This option decides which allocator is to be analyzed if neither 558 '--slab' nor '--page' option is used. Default is 'slab'. 559 560record.*:: 561 record.build-id:: 562 This option can be 'cache', 'no-cache', 'skip' or 'mmap'. 563 'cache' is to post-process data and save/update the binaries into 564 the build-id cache (in ~/.debug). This is the default. 565 But if this option is 'no-cache', it will not update the build-id cache. 566 'skip' skips post-processing and does not update the cache. 567 'mmap' skips post-processing and reads build-ids from MMAP events. 568 569 record.call-graph:: 570 This is identical to 'call-graph.record-mode', except it is 571 applicable only for 'record' subcommand. This option ONLY setup 572 the unwind method. To enable 'perf record' to actually use it, 573 the command line option -g must be specified. 574 575 record.aio:: 576 Use 'n' control blocks in asynchronous (Posix AIO) trace writing 577 mode ('n' default: 1, max: 4). 578 579diff.*:: 580 diff.order:: 581 This option sets the number of columns to sort the result. 582 The default is 0, which means sorting by baseline. 583 Setting it to 1 will sort the result by delta (or other 584 compute method selected). 585 586 diff.compute:: 587 This options sets the method for computing the diff result. 588 Possible values are 'delta', 'delta-abs', 'ratio' and 589 'wdiff'. Default is 'delta'. 590 591trace.*:: 592 trace.add_events:: 593 Allows adding a set of events to add to the ones specified 594 by the user, or use as a default one if none was specified. 595 The initial use case is to add augmented_raw_syscalls.o to 596 activate the 'perf trace' logic that looks for syscall 597 pointer contents after the normal tracepoint payload. 598 599 trace.args_alignment:: 600 Number of columns to align the argument list, default is 70, 601 use 40 for the strace default, zero to no alignment. 602 603 trace.no_inherit:: 604 Do not follow children threads. 605 606 trace.show_arg_names:: 607 Should syscall argument names be printed? If not then trace.show_zeros 608 will be set. 609 610 trace.show_duration:: 611 Show syscall duration. 612 613 trace.show_prefix:: 614 If set to 'yes' will show common string prefixes in tables. The default 615 is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED". 616 617 trace.show_timestamp:: 618 Show syscall start timestamp. 619 620 trace.show_zeros:: 621 Do not suppress syscall arguments that are equal to zero. 622 623 trace.tracepoint_beautifiers:: 624 Use "libtraceevent" to use that library to augment the tracepoint arguments, 625 "libbeauty", the default, to use the same argument beautifiers used in the 626 strace-like sys_enter+sys_exit lines. 627 628ftrace.*:: 629 ftrace.tracer:: 630 Can be used to select the default tracer when neither -G nor 631 -F option is not specified. Possible values are 'function' and 632 'function_graph'. 633 634llvm.*:: 635 llvm.clang-path:: 636 Path to clang. If omit, search it from $PATH. 637 638 llvm.clang-bpf-cmd-template:: 639 Cmdline template. Below lines show its default value. Environment 640 variable is used to pass options. 641 "$CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS "\ 642 "-DLINUX_VERSION_CODE=$LINUX_VERSION_CODE " \ 643 "$CLANG_OPTIONS $PERF_BPF_INC_OPTIONS $KERNEL_INC_OPTIONS " \ 644 "-Wno-unused-value -Wno-pointer-sign " \ 645 "-working-directory $WORKING_DIR " \ 646 "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -O2 -o - $LLVM_OPTIONS_PIPE" 647 648 llvm.clang-opt:: 649 Options passed to clang. 650 651 llvm.kbuild-dir:: 652 kbuild directory. If not set, use /lib/modules/`uname -r`/build. 653 If set to "" deliberately, skip kernel header auto-detector. 654 655 llvm.kbuild-opts:: 656 Options passed to 'make' when detecting kernel header options. 657 658 llvm.dump-obj:: 659 Enable perf dump BPF object files compiled by LLVM. 660 661 llvm.opts:: 662 Options passed to llc. 663 664samples.*:: 665 666 samples.context:: 667 Define how many ns worth of time to show 668 around samples in perf report sample context browser. 669 670scripts.*:: 671 672 Any option defines a script that is added to the scripts menu 673 in the interactive perf browser and whose output is displayed. 674 The name of the option is the name, the value is a script command line. 675 The script gets the same options passed as a full perf script, 676 in particular -i perfdata file, --cpu, --tid 677 678convert.*:: 679 680 convert.queue-size:: 681 Limit the size of ordered_events queue, so we could control 682 allocation size of perf data files without proper finished 683 round events. 684stat.*:: 685 686 stat.big-num:: 687 (boolean) Change the default for "--big-num". To make 688 "--no-big-num" the default, set "stat.big-num=false". 689 690intel-pt.*:: 691 692 intel-pt.cache-divisor:: 693 694 intel-pt.mispred-all:: 695 If set, Intel PT decoder will set the mispred flag on all 696 branches. 697 698auxtrace.*:: 699 700 auxtrace.dumpdir:: 701 s390 only. The directory to save the auxiliary trace buffer 702 can be changed using this option. Ex, auxtrace.dumpdir=/tmp. 703 If the directory does not exist or has the wrong file type, 704 the current directory is used. 705 706daemon.*:: 707 708 daemon.base:: 709 Base path for daemon data. All sessions data are stored under 710 this path. 711 712session-<NAME>.*:: 713 714 session-<NAME>.run:: 715 716 Defines new record session for daemon. The value is record's 717 command line without the 'record' keyword. 718 719 720SEE ALSO 721-------- 722linkperf:perf[1] 723