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