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