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