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 When sub-commands 'top' and 'report' work with -g/—-children 409 there're options in control of call-graph. 410 411 call-graph.record-mode:: 412 The record-mode can be 'fp' (frame pointer), 'dwarf' and 'lbr'. 413 The value of 'dwarf' is effective only if perf detect needed library 414 (libunwind or a recent version of libdw). 415 'lbr' only work for cpus that support it. 416 417 call-graph.dump-size:: 418 The size of stack to dump in order to do post-unwinding. Default is 8192 (byte). 419 When using dwarf into record-mode, the default size will be used if omitted. 420 421 call-graph.print-type:: 422 The print-types can be graph (graph absolute), fractal (graph relative), 423 flat and folded. This option controls a way to show overhead for each callchain 424 entry. Suppose a following example. 425 426 Overhead Symbols 427 ........ ....... 428 40.00% foo 429 | 430 ---foo 431 | 432 |--50.00%--bar 433 | main 434 | 435 --50.00%--baz 436 main 437 438 This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly 439 half and half so 'fractal' shows 50.00% for each 440 (meaning that it assumes 100% total overhead of 'foo'). 441 442 The 'graph' uses absolute overhead value of 'foo' as total so each of 443 'bar' and 'baz' callchain will have 20.00% of overhead. 444 If 'flat' is used, single column and linear exposure of call chains. 445 'folded' mean call chains are displayed in a line, separated by semicolons. 446 447 call-graph.order:: 448 This option controls print order of callchains. The default is 449 'callee' which means callee is printed at top and then followed by its 450 caller and so on. The 'caller' prints it in reverse order. 451 452 If this option is not set and report.children or top.children is 453 set to true (or the equivalent command line option is given), 454 the default value of this option is changed to 'caller' for the 455 execution of 'perf report' or 'perf top'. Other commands will 456 still default to 'callee'. 457 458 call-graph.sort-key:: 459 The callchains are merged if they contain same information. 460 The sort-key option determines a way to compare the callchains. 461 A value of 'sort-key' can be 'function' or 'address'. 462 The default is 'function'. 463 464 call-graph.threshold:: 465 When there're many callchains it'd print tons of lines. So perf omits 466 small callchains under a certain overhead (threshold) and this option 467 control the threshold. Default is 0.5 (%). The overhead is calculated 468 by value depends on call-graph.print-type. 469 470 call-graph.print-limit:: 471 This is a maximum number of lines of callchain printed for a single 472 histogram entry. Default is 0 which means no limitation. 473 474report.*:: 475 report.sort_order:: 476 Allows changing the default sort order from "comm,dso,symbol" to 477 some other default, for instance "sym,dso" may be more fitting for 478 kernel developers. 479 report.percent-limit:: 480 This one is mostly the same as call-graph.threshold but works for 481 histogram entries. Entries having an overhead lower than this 482 percentage will not be printed. Default is '0'. If percent-limit 483 is '10', only entries which have more than 10% of overhead will be 484 printed. 485 486 report.queue-size:: 487 This option sets up the maximum allocation size of the internal 488 event queue for ordering events. Default is 0, meaning no limit. 489 490 report.children:: 491 'Children' means functions called from another function. 492 If this option is true, 'perf report' cumulates callchains of children 493 and show (accumulated) total overhead as well as 'Self' overhead. 494 Please refer to the 'perf report' manual. The default is 'true'. 495 496 report.group:: 497 This option is to show event group information together. 498 Example output with this turned on, notice that there is one column 499 per event in the group, ref-cycles and cycles: 500 501 # group: {ref-cycles,cycles} 502 # ======== 503 # 504 # Samples: 7K of event 'anon group { ref-cycles, cycles }' 505 # Event count (approx.): 6876107743 506 # 507 # Overhead Command Shared Object Symbol 508 # ................ ....... ................. ................... 509 # 510 99.84% 99.76% noploop noploop [.] main 511 0.07% 0.00% noploop ld-2.15.so [.] strcmp 512 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del 513 514top.*:: 515 top.children:: 516 Same as 'report.children'. So if it is enabled, the output of 'top' 517 command will have 'Children' overhead column as well as 'Self' overhead 518 column by default. 519 The default is 'true'. 520 521 top.call-graph:: 522 This is identical to 'call-graph.record-mode', except it is 523 applicable only for 'top' subcommand. This option ONLY setup 524 the unwind method. To enable 'perf top' to actually use it, 525 the command line option -g must be specified. 526 527man.*:: 528 man.viewer:: 529 This option can assign a tool to view manual pages when 'help' 530 subcommand was invoked. Supported tools are 'man', 'woman' 531 (with emacs client) and 'konqueror'. Default is 'man'. 532 533 New man viewer tool can be also added using 'man.<tool>.cmd' 534 or use different path using 'man.<tool>.path' config option. 535 536pager.*:: 537 pager.<subcommand>:: 538 When the subcommand is run on stdio, determine whether it uses 539 pager or not based on this value. Default is 'unspecified'. 540 541kmem.*:: 542 kmem.default:: 543 This option decides which allocator is to be analyzed if neither 544 '--slab' nor '--page' option is used. Default is 'slab'. 545 546record.*:: 547 record.build-id:: 548 This option can be 'cache', 'no-cache' or 'skip'. 549 'cache' is to post-process data and save/update the binaries into 550 the build-id cache (in ~/.debug). This is the default. 551 But if this option is 'no-cache', it will not update the build-id cache. 552 'skip' skips post-processing and does not update the cache. 553 554 record.call-graph:: 555 This is identical to 'call-graph.record-mode', except it is 556 applicable only for 'record' subcommand. This option ONLY setup 557 the unwind method. To enable 'perf record' to actually use it, 558 the command line option -g must be specified. 559 560 record.aio:: 561 Use 'n' control blocks in asynchronous (Posix AIO) trace writing 562 mode ('n' default: 1, max: 4). 563 564diff.*:: 565 diff.order:: 566 This option sets the number of columns to sort the result. 567 The default is 0, which means sorting by baseline. 568 Setting it to 1 will sort the result by delta (or other 569 compute method selected). 570 571 diff.compute:: 572 This options sets the method for computing the diff result. 573 Possible values are 'delta', 'delta-abs', 'ratio' and 574 'wdiff'. Default is 'delta'. 575 576trace.*:: 577 trace.add_events:: 578 Allows adding a set of events to add to the ones specified 579 by the user, or use as a default one if none was specified. 580 The initial use case is to add augmented_raw_syscalls.o to 581 activate the 'perf trace' logic that looks for syscall 582 pointer contents after the normal tracepoint payload. 583 584 trace.args_alignment:: 585 Number of columns to align the argument list, default is 70, 586 use 40 for the strace default, zero to no alignment. 587 588 trace.no_inherit:: 589 Do not follow children threads. 590 591 trace.show_arg_names:: 592 Should syscall argument names be printed? If not then trace.show_zeros 593 will be set. 594 595 trace.show_duration:: 596 Show syscall duration. 597 598 trace.show_prefix:: 599 If set to 'yes' will show common string prefixes in tables. The default 600 is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED". 601 602 trace.show_timestamp:: 603 Show syscall start timestamp. 604 605 trace.show_zeros:: 606 Do not suppress syscall arguments that are equal to zero. 607 608 trace.tracepoint_beautifiers:: 609 Use "libtraceevent" to use that library to augment the tracepoint arguments, 610 "libbeauty", the default, to use the same argument beautifiers used in the 611 strace-like sys_enter+sys_exit lines. 612 613ftrace.*:: 614 ftrace.tracer:: 615 Can be used to select the default tracer. Possible values are 616 'function' and 'function_graph'. 617 618llvm.*:: 619 llvm.clang-path:: 620 Path to clang. If omit, search it from $PATH. 621 622 llvm.clang-bpf-cmd-template:: 623 Cmdline template. Below lines show its default value. Environment 624 variable is used to pass options. 625 "$CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS "\ 626 "-DLINUX_VERSION_CODE=$LINUX_VERSION_CODE " \ 627 "$CLANG_OPTIONS $PERF_BPF_INC_OPTIONS $KERNEL_INC_OPTIONS " \ 628 "-Wno-unused-value -Wno-pointer-sign " \ 629 "-working-directory $WORKING_DIR " \ 630 "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -O2 -o - $LLVM_OPTIONS_PIPE" 631 632 llvm.clang-opt:: 633 Options passed to clang. 634 635 llvm.kbuild-dir:: 636 kbuild directory. If not set, use /lib/modules/`uname -r`/build. 637 If set to "" deliberately, skip kernel header auto-detector. 638 639 llvm.kbuild-opts:: 640 Options passed to 'make' when detecting kernel header options. 641 642 llvm.dump-obj:: 643 Enable perf dump BPF object files compiled by LLVM. 644 645 llvm.opts:: 646 Options passed to llc. 647 648samples.*:: 649 650 samples.context:: 651 Define how many ns worth of time to show 652 around samples in perf report sample context browser. 653 654scripts.*:: 655 656 Any option defines a script that is added to the scripts menu 657 in the interactive perf browser and whose output is displayed. 658 The name of the option is the name, the value is a script command line. 659 The script gets the same options passed as a full perf script, 660 in particular -i perfdata file, --cpu, --tid 661 662convert.*:: 663 664 convert.queue-size:: 665 Limit the size of ordered_events queue, so we could control 666 allocation size of perf data files without proper finished 667 round events. 668 669intel-pt.*:: 670 671 intel-pt.cache-divisor:: 672 673 intel-pt.mispred-all:: 674 If set, Intel PT decoder will set the mispred flag on all 675 branches. 676 677auxtrace.*:: 678 679 auxtrace.dumpdir:: 680 s390 only. The directory to save the auxiliary trace buffer 681 can be changed using this option. Ex, auxtrace.dumpdir=/tmp. 682 If the directory does not exist or has the wrong file type, 683 the current directory is used. 684 685SEE ALSO 686-------- 687linkperf:perf[1] 688