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>] -l | --list 12 13DESCRIPTION 14----------- 15You can manage variables in a configuration file with this command. 16 17OPTIONS 18------- 19 20-l:: 21--list:: 22 Show current config variables, name and value, for all sections. 23 24--user:: 25 For writing and reading options: write to user 26 '$HOME/.perfconfig' file or read it. 27 28--system:: 29 For writing and reading options: write to system-wide 30 '$(sysconfdir)/perfconfig' or read it. 31 32CONFIGURATION FILE 33------------------ 34 35The perf configuration file contains many variables to change various 36aspects of each of its tools, including output, disk usage, etc. 37The '$HOME/.perfconfig' file is used to store a per-user configuration. 38The file '$(sysconfdir)/perfconfig' can be used to 39store a system-wide default configuration. 40 41When reading or writing, the values are read from the system and user 42configuration files by default, and options '--system' and '--user' 43can be used to tell the command to read from or write to only that location. 44 45Syntax 46~~~~~~ 47 48The file consist of sections. A section starts with its name 49surrounded by square brackets and continues till the next section 50begins. Each variable must be in a section, and have the form 51'name = value', for example: 52 53 [section] 54 name1 = value1 55 name2 = value2 56 57Section names are case sensitive and can contain any characters except 58newline (double quote `"` and backslash have to be escaped as `\"` and `\\`, 59respectively). Section headers can't span multiple lines. 60 61Example 62~~~~~~~ 63 64Given a $HOME/.perfconfig like this: 65 66# 67# This is the config file, and 68# a '#' and ';' character indicates a comment 69# 70 71 [colors] 72 # Color variables 73 top = red, default 74 medium = green, default 75 normal = lightgray, default 76 selected = white, lightgray 77 jump_arrows = blue, default 78 addr = magenta, default 79 root = white, blue 80 81 [tui] 82 # Defaults if linked with libslang 83 report = on 84 annotate = on 85 top = on 86 87 [buildid] 88 # Default, disable using /dev/null 89 dir = ~/.debug 90 91 [annotate] 92 # Defaults 93 hide_src_code = false 94 use_offset = true 95 jump_arrows = true 96 show_nr_jumps = false 97 98 [help] 99 # Format can be man, info, web or html 100 format = man 101 autocorrect = 0 102 103 [ui] 104 show-headers = true 105 106 [call-graph] 107 # fp (framepointer), dwarf 108 record-mode = fp 109 print-type = graph 110 order = caller 111 sort-key = function 112 113 [report] 114 # Defaults 115 sort-order = comm,dso,symbol 116 percent-limit = 0 117 queue-size = 0 118 children = true 119 group = true 120 121Variables 122~~~~~~~~~ 123 124colors.*:: 125 The variables for customizing the colors used in the output for the 126 'report', 'top' and 'annotate' in the TUI. They should specify the 127 foreground and background colors, separated by a comma, for example: 128 129 medium = green, lightgray 130 131 If you want to use the color configured for you terminal, just leave it 132 as 'default', for example: 133 134 medium = default, lightgray 135 136 Available colors: 137 red, yellow, green, cyan, gray, black, blue, 138 white, default, magenta, lightgray 139 140 colors.top:: 141 'top' means a overhead percentage which is more than 5%. 142 And values of this variable specify percentage colors. 143 Basic key values are foreground-color 'red' and 144 background-color 'default'. 145 colors.medium:: 146 'medium' means a overhead percentage which has more than 0.5%. 147 Default values are 'green' and 'default'. 148 colors.normal:: 149 'normal' means the rest of overhead percentages 150 except 'top', 'medium', 'selected'. 151 Default values are 'lightgray' and 'default'. 152 colors.selected:: 153 This selects the colors for the current entry in a list of entries 154 from sub-commands (top, report, annotate). 155 Default values are 'black' and 'lightgray'. 156 colors.jump_arrows:: 157 Colors for jump arrows on assembly code listings 158 such as 'jns', 'jmp', 'jane', etc. 159 Default values are 'blue', 'default'. 160 colors.addr:: 161 This selects colors for addresses from 'annotate'. 162 Default values are 'magenta', 'default'. 163 colors.root:: 164 Colors for headers in the output of a sub-commands (top, report). 165 Default values are 'white', 'blue'. 166 167tui.*, gtk.*:: 168 Subcommands that can be configured here are 'top', 'report' and 'annotate'. 169 These values are booleans, for example: 170 171 [tui] 172 top = true 173 174 will make the TUI be the default for the 'top' subcommand. Those will be 175 available if the required libs were detected at tool build time. 176 177buildid.*:: 178 buildid.dir:: 179 Each executable and shared library in modern distributions comes with a 180 content based identifier that, if available, will be inserted in a 181 'perf.data' file header to, at analysis time find what is needed to do 182 symbol resolution, code annotation, etc. 183 184 The recording tools also stores a hard link or copy in a per-user 185 directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms 186 and /proc/kcore files to be used at analysis time. 187 188 The buildid.dir variable can be used to either change this directory 189 cache location, or to disable it altogether. If you want to disable it, 190 set buildid.dir to /dev/null. The default is $HOME/.debug 191 192annotate.*:: 193 These options work only for TUI. 194 These are in control of addresses, jump function, source code 195 in lines of assembly code from a specific program. 196 197 annotate.hide_src_code:: 198 If a program which is analyzed has source code, 199 this option lets 'annotate' print a list of assembly code with the source code. 200 For example, let's see a part of a program. There're four lines. 201 If this option is 'true', they can be printed 202 without source code from a program as below. 203 204 │ push %rbp 205 │ mov %rsp,%rbp 206 │ sub $0x10,%rsp 207 │ mov (%rdi),%rdx 208 209 But if this option is 'false', source code of the part 210 can be also printed as below. Default is 'false'. 211 212 │ struct rb_node *rb_next(const struct rb_node *node) 213 │ { 214 │ push %rbp 215 │ mov %rsp,%rbp 216 │ sub $0x10,%rsp 217 │ struct rb_node *parent; 218 │ 219 │ if (RB_EMPTY_NODE(node)) 220 │ mov (%rdi),%rdx 221 │ return n; 222 223 annotate.use_offset:: 224 Basing on a first address of a loaded function, offset can be used. 225 Instead of using original addresses of assembly code, 226 addresses subtracted from a base address can be printed. 227 Let's illustrate an example. 228 If a base address is 0XFFFFFFFF81624d50 as below, 229 230 ffffffff81624d50 <load0> 231 232 an address on assembly code has a specific absolute address as below 233 234 ffffffff816250b8:│ mov 0x8(%r14),%rdi 235 236 but if use_offset is 'true', an address subtracted from a base address is printed. 237 Default is true. This option is only applied to TUI. 238 239 368:│ mov 0x8(%r14),%rdi 240 241 annotate.jump_arrows:: 242 There can be jump instruction among assembly code. 243 Depending on a boolean value of jump_arrows, 244 arrows can be printed or not which represent 245 where do the instruction jump into as below. 246 247 │ ┌──jmp 1333 248 │ │ xchg %ax,%ax 249 │1330:│ mov %r15,%r10 250 │1333:└─→cmp %r15,%r14 251 252 If jump_arrow is 'false', the arrows isn't printed as below. 253 Default is 'false'. 254 255 │ ↓ jmp 1333 256 │ xchg %ax,%ax 257 │1330: mov %r15,%r10 258 │1333: cmp %r15,%r14 259 260 annotate.show_linenr:: 261 When showing source code if this option is 'true', 262 line numbers are printed as below. 263 264 │1628 if (type & PERF_SAMPLE_IDENTIFIER) { 265 │ ↓ jne 508 266 │1628 data->id = *array; 267 │1629 array++; 268 │1630 } 269 270 However if this option is 'false', they aren't printed as below. 271 Default is 'false'. 272 273 │ if (type & PERF_SAMPLE_IDENTIFIER) { 274 │ ↓ jne 508 275 │ data->id = *array; 276 │ array++; 277 │ } 278 279 annotate.show_nr_jumps:: 280 Let's see a part of assembly code. 281 282 │1382: movb $0x1,-0x270(%rbp) 283 284 If use this, the number of branches jumping to that address can be printed as below. 285 Default is 'false'. 286 287 │1 1382: movb $0x1,-0x270(%rbp) 288 289 annotate.show_total_period:: 290 To compare two records on an instruction base, with this option 291 provided, display total number of samples that belong to a line 292 in assembly code. If this option is 'true', total periods are printed 293 instead of percent values as below. 294 295 302 │ mov %eax,%eax 296 297 But if this option is 'false', percent values for overhead are printed i.e. 298 Default is 'false'. 299 300 99.93 │ mov %eax,%eax 301 302hist.*:: 303 hist.percentage:: 304 This option control the way to calculate overhead of filtered entries - 305 that means the value of this option is effective only if there's a 306 filter (by comm, dso or symbol name). Suppose a following example: 307 308 Overhead Symbols 309 ........ ....... 310 33.33% foo 311 33.33% bar 312 33.33% baz 313 314 This is an original overhead and we'll filter out the first 'foo' 315 entry. The value of 'relative' would increase the overhead of 'bar' 316 and 'baz' to 50.00% for each, while 'absolute' would show their 317 current overhead (33.33%). 318 319ui.*:: 320 ui.show-headers:: 321 This option controls display of column headers (like 'Overhead' and 'Symbol') 322 in 'report' and 'top'. If this option is false, they are hidden. 323 This option is only applied to TUI. 324 325call-graph.*:: 326 When sub-commands 'top' and 'report' work with -g/—-children 327 there're options in control of call-graph. 328 329 call-graph.record-mode:: 330 The record-mode can be 'fp' (frame pointer), 'dwarf' and 'lbr'. 331 The value of 'dwarf' is effective only if perf detect needed library 332 (libunwind or a recent version of libdw). 333 'lbr' only work for cpus that support it. 334 335 call-graph.dump-size:: 336 The size of stack to dump in order to do post-unwinding. Default is 8192 (byte). 337 When using dwarf into record-mode, the default size will be used if omitted. 338 339 call-graph.print-type:: 340 The print-types can be graph (graph absolute), fractal (graph relative), 341 flat and folded. This option controls a way to show overhead for each callchain 342 entry. Suppose a following example. 343 344 Overhead Symbols 345 ........ ....... 346 40.00% foo 347 | 348 ---foo 349 | 350 |--50.00%--bar 351 | main 352 | 353 --50.00%--baz 354 main 355 356 This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly 357 half and half so 'fractal' shows 50.00% for each 358 (meaning that it assumes 100% total overhead of 'foo'). 359 360 The 'graph' uses absolute overhead value of 'foo' as total so each of 361 'bar' and 'baz' callchain will have 20.00% of overhead. 362 If 'flat' is used, single column and linear exposure of call chains. 363 'folded' mean call chains are displayed in a line, separated by semicolons. 364 365 call-graph.order:: 366 This option controls print order of callchains. The default is 367 'callee' which means callee is printed at top and then followed by its 368 caller and so on. The 'caller' prints it in reverse order. 369 370 If this option is not set and report.children or top.children is 371 set to true (or the equivalent command line option is given), 372 the default value of this option is changed to 'caller' for the 373 execution of 'perf report' or 'perf top'. Other commands will 374 still default to 'callee'. 375 376 call-graph.sort-key:: 377 The callchains are merged if they contain same information. 378 The sort-key option determines a way to compare the callchains. 379 A value of 'sort-key' can be 'function' or 'address'. 380 The default is 'function'. 381 382 call-graph.threshold:: 383 When there're many callchains it'd print tons of lines. So perf omits 384 small callchains under a certain overhead (threshold) and this option 385 control the threshold. Default is 0.5 (%). The overhead is calculated 386 by value depends on call-graph.print-type. 387 388 call-graph.print-limit:: 389 This is a maximum number of lines of callchain printed for a single 390 histogram entry. Default is 0 which means no limitation. 391 392report.*:: 393 report.sort_order:: 394 Allows changing the default sort order from "comm,dso,symbol" to 395 some other default, for instance "sym,dso" may be more fitting for 396 kernel developers. 397 report.percent-limit:: 398 This one is mostly the same as call-graph.threshold but works for 399 histogram entries. Entries having an overhead lower than this 400 percentage will not be printed. Default is '0'. If percent-limit 401 is '10', only entries which have more than 10% of overhead will be 402 printed. 403 404 report.queue-size:: 405 This option sets up the maximum allocation size of the internal 406 event queue for ordering events. Default is 0, meaning no limit. 407 408 report.children:: 409 'Children' means functions called from another function. 410 If this option is true, 'perf report' cumulates callchains of children 411 and show (accumulated) total overhead as well as 'Self' overhead. 412 Please refer to the 'perf report' manual. The default is 'true'. 413 414 report.group:: 415 This option is to show event group information together. 416 Example output with this turned on, notice that there is one column 417 per event in the group, ref-cycles and cycles: 418 419 # group: {ref-cycles,cycles} 420 # ======== 421 # 422 # Samples: 7K of event 'anon group { ref-cycles, cycles }' 423 # Event count (approx.): 6876107743 424 # 425 # Overhead Command Shared Object Symbol 426 # ................ ....... ................. ................... 427 # 428 99.84% 99.76% noploop noploop [.] main 429 0.07% 0.00% noploop ld-2.15.so [.] strcmp 430 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del 431 432top.*:: 433 top.children:: 434 Same as 'report.children'. So if it is enabled, the output of 'top' 435 command will have 'Children' overhead column as well as 'Self' overhead 436 column by default. 437 The default is 'true'. 438 439man.*:: 440 man.viewer:: 441 This option can assign a tool to view manual pages when 'help' 442 subcommand was invoked. Supported tools are 'man', 'woman' 443 (with emacs client) and 'konqueror'. Default is 'man'. 444 445 New man viewer tool can be also added using 'man.<tool>.cmd' 446 or use different path using 'man.<tool>.path' config option. 447 448pager.*:: 449 pager.<subcommand>:: 450 When the subcommand is run on stdio, determine whether it uses 451 pager or not based on this value. Default is 'unspecified'. 452 453kmem.*:: 454 kmem.default:: 455 This option decides which allocator is to be analyzed if neither 456 '--slab' nor '--page' option is used. Default is 'slab'. 457 458record.*:: 459 record.build-id:: 460 This option can be 'cache', 'no-cache' or 'skip'. 461 'cache' is to post-process data and save/update the binaries into 462 the build-id cache (in ~/.debug). This is the default. 463 But if this option is 'no-cache', it will not update the build-id cache. 464 'skip' skips post-processing and does not update the cache. 465 466SEE ALSO 467-------- 468linkperf:perf[1] 469