| perf-config(1) |
| ============== |
| |
| NAME |
| ---- |
| perf-config - Get and set variables in a configuration file. |
| |
| SYNOPSIS |
| -------- |
| [verse] |
| 'perf config' [<file-option>] [section.name[=value] ...] |
| or |
| 'perf config' [<file-option>] -l | --list |
| |
| DESCRIPTION |
| ----------- |
| You can manage variables in a configuration file with this command. |
| |
| OPTIONS |
| ------- |
| |
| -l:: |
| --list:: |
| Show current config variables, name and value, for all sections. |
| |
| --user:: |
| For writing and reading options: write to user |
| '$HOME/.perfconfig' file or read it. |
| |
| --system:: |
| For writing and reading options: write to system-wide |
| '$(sysconfdir)/perfconfig' or read it. |
| |
| CONFIGURATION FILE |
| ------------------ |
| |
| The perf configuration file contains many variables to change various |
| aspects of each of its tools, including output, disk usage, etc. |
| The '$HOME/.perfconfig' file is used to store a per-user configuration. |
| The file '$(sysconfdir)/perfconfig' can be used to |
| store a system-wide default configuration. |
| |
| One an disable reading config files by setting the PERF_CONFIG environment |
| variable to /dev/null, or provide an alternate config file by setting that |
| variable. |
| |
| When reading or writing, the values are read from the system and user |
| configuration files by default, and options '--system' and '--user' |
| can be used to tell the command to read from or write to only that location. |
| |
| Syntax |
| ~~~~~~ |
| |
| The file consist of sections. A section starts with its name |
| surrounded by square brackets and continues till the next section |
| begins. Each variable must be in a section, and have the form |
| 'name = value', for example: |
| |
| [section] |
| name1 = value1 |
| name2 = value2 |
| |
| Section names are case sensitive and can contain any characters except |
| newline (double quote `"` and backslash have to be escaped as `\"` and `\\`, |
| respectively). Section headers can't span multiple lines. |
| |
| Example |
| ~~~~~~~ |
| |
| Given a $HOME/.perfconfig like this: |
| |
| # |
| # This is the config file, and |
| # a '#' and ';' character indicates a comment |
| # |
| |
| [colors] |
| # Color variables |
| top = red, default |
| medium = green, default |
| normal = lightgray, default |
| selected = white, lightgray |
| jump_arrows = blue, default |
| addr = magenta, default |
| root = white, blue |
| |
| [tui] |
| # Defaults if linked with libslang |
| report = on |
| annotate = on |
| top = on |
| |
| [buildid] |
| # Default, disable using /dev/null |
| dir = ~/.debug |
| |
| [annotate] |
| # Defaults |
| hide_src_code = false |
| use_offset = true |
| jump_arrows = true |
| show_nr_jumps = false |
| |
| [help] |
| # Format can be man, info, web or html |
| format = man |
| autocorrect = 0 |
| |
| [ui] |
| show-headers = true |
| |
| [call-graph] |
| # fp (framepointer), dwarf |
| record-mode = fp |
| print-type = graph |
| order = caller |
| sort-key = function |
| |
| [report] |
| # Defaults |
| sort_order = comm,dso,symbol |
| percent-limit = 0 |
| queue-size = 0 |
| children = true |
| group = true |
| |
| [llvm] |
| dump-obj = true |
| clang-opt = -g |
| |
| You can hide source code of annotate feature setting the config to false with |
| |
| % perf config annotate.hide_src_code=true |
| |
| If you want to add or modify several config items, you can do like |
| |
| % perf config ui.show-headers=false kmem.default=slab |
| |
| To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do |
| |
| % perf config --user report sort-order=srcline |
| |
| To change colors of selected line to other foreground and background colors |
| in system config file (i.e. `$(sysconf)/perfconfig`), do |
| |
| % perf config --system colors.selected=yellow,green |
| |
| To query the record mode of call graph, do |
| |
| % perf config call-graph.record-mode |
| |
| If you want to know multiple config key/value pairs, you can do like |
| |
| % perf config report.queue-size call-graph.order report.children |
| |
| To query the config value of sort order of call graph in user config file (i.e. `~/.perfconfig`), do |
| |
| % perf config --user call-graph.sort-order |
| |
| To query the config value of buildid directory in system config file (i.e. `$(sysconf)/perfconfig`), do |
| |
| % perf config --system buildid.dir |
| |
| Variables |
| ~~~~~~~~~ |
| |
| colors.*:: |
| The variables for customizing the colors used in the output for the |
| 'report', 'top' and 'annotate' in the TUI. They should specify the |
| foreground and background colors, separated by a comma, for example: |
| |
| medium = green, lightgray |
| |
| If you want to use the color configured for you terminal, just leave it |
| as 'default', for example: |
| |
| medium = default, lightgray |
| |
| Available colors: |
| red, yellow, green, cyan, gray, black, blue, |
| white, default, magenta, lightgray |
| |
| colors.top:: |
| 'top' means a overhead percentage which is more than 5%. |
| And values of this variable specify percentage colors. |
| Basic key values are foreground-color 'red' and |
| background-color 'default'. |
| colors.medium:: |
| 'medium' means a overhead percentage which has more than 0.5%. |
| Default values are 'green' and 'default'. |
| colors.normal:: |
| 'normal' means the rest of overhead percentages |
| except 'top', 'medium', 'selected'. |
| Default values are 'lightgray' and 'default'. |
| colors.selected:: |
| This selects the colors for the current entry in a list of entries |
| from sub-commands (top, report, annotate). |
| Default values are 'black' and 'lightgray'. |
| colors.jump_arrows:: |
| Colors for jump arrows on assembly code listings |
| such as 'jns', 'jmp', 'jane', etc. |
| Default values are 'blue', 'default'. |
| colors.addr:: |
| This selects colors for addresses from 'annotate'. |
| Default values are 'magenta', 'default'. |
| colors.root:: |
| Colors for headers in the output of a sub-commands (top, report). |
| Default values are 'white', 'blue'. |
| |
| core.*:: |
| core.proc-map-timeout:: |
| Sets a timeout (in milliseconds) for parsing /proc/<pid>/maps files. |
| Can be overridden by the --proc-map-timeout option on supported |
| subcommands. The default timeout is 500ms. |
| |
| tui.*, gtk.*:: |
| Subcommands that can be configured here are 'top', 'report' and 'annotate'. |
| These values are booleans, for example: |
| |
| [tui] |
| top = true |
| |
| will make the TUI be the default for the 'top' subcommand. Those will be |
| available if the required libs were detected at tool build time. |
| |
| buildid.*:: |
| buildid.dir:: |
| Each executable and shared library in modern distributions comes with a |
| content based identifier that, if available, will be inserted in a |
| 'perf.data' file header to, at analysis time find what is needed to do |
| symbol resolution, code annotation, etc. |
| |
| The recording tools also stores a hard link or copy in a per-user |
| directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms |
| and /proc/kcore files to be used at analysis time. |
| |
| The buildid.dir variable can be used to either change this directory |
| cache location, or to disable it altogether. If you want to disable it, |
| set buildid.dir to /dev/null. The default is $HOME/.debug |
| |
| annotate.*:: |
| These are in control of addresses, jump function, source code |
| in lines of assembly code from a specific program. |
| |
| annotate.hide_src_code:: |
| If a program which is analyzed has source code, |
| this option lets 'annotate' print a list of assembly code with the source code. |
| For example, let's see a part of a program. There're four lines. |
| If this option is 'true', they can be printed |
| without source code from a program as below. |
| |
| │ push %rbp |
| │ mov %rsp,%rbp |
| │ sub $0x10,%rsp |
| │ mov (%rdi),%rdx |
| |
| But if this option is 'false', source code of the part |
| can be also printed as below. Default is 'false'. |
| |
| │ struct rb_node *rb_next(const struct rb_node *node) |
| │ { |
| │ push %rbp |
| │ mov %rsp,%rbp |
| │ sub $0x10,%rsp |
| │ struct rb_node *parent; |
| │ |
| │ if (RB_EMPTY_NODE(node)) |
| │ mov (%rdi),%rdx |
| │ return n; |
| |
| This option works with tui, stdio2 browsers. |
| |
| annotate.use_offset:: |
| Basing on a first address of a loaded function, offset can be used. |
| Instead of using original addresses of assembly code, |
| addresses subtracted from a base address can be printed. |
| Let's illustrate an example. |
| If a base address is 0XFFFFFFFF81624d50 as below, |
| |
| ffffffff81624d50 <load0> |
| |
| an address on assembly code has a specific absolute address as below |
| |
| ffffffff816250b8:│ mov 0x8(%r14),%rdi |
| |
| but if use_offset is 'true', an address subtracted from a base address is printed. |
| Default is true. This option is only applied to TUI. |
| |
| 368:│ mov 0x8(%r14),%rdi |
| |
| This option works with tui, stdio2 browsers. |
| |
| annotate.jump_arrows:: |
| There can be jump instruction among assembly code. |
| Depending on a boolean value of jump_arrows, |
| arrows can be printed or not which represent |
| where do the instruction jump into as below. |
| |
| │ ┌──jmp 1333 |
| │ │ xchg %ax,%ax |
| │1330:│ mov %r15,%r10 |
| │1333:└─→cmp %r15,%r14 |
| |
| If jump_arrow is 'false', the arrows isn't printed as below. |
| Default is 'false'. |
| |
| │ ↓ jmp 1333 |
| │ xchg %ax,%ax |
| │1330: mov %r15,%r10 |
| │1333: cmp %r15,%r14 |
| |
| This option works with tui browser. |
| |
| annotate.show_linenr:: |
| When showing source code if this option is 'true', |
| line numbers are printed as below. |
| |
| │1628 if (type & PERF_SAMPLE_IDENTIFIER) { |
| │ ↓ jne 508 |
| │1628 data->id = *array; |
| │1629 array++; |
| │1630 } |
| |
| However if this option is 'false', they aren't printed as below. |
| Default is 'false'. |
| |
| │ if (type & PERF_SAMPLE_IDENTIFIER) { |
| │ ↓ jne 508 |
| │ data->id = *array; |
| │ array++; |
| │ } |
| |
| This option works with tui, stdio2 browsers. |
| |
| annotate.show_nr_jumps:: |
| Let's see a part of assembly code. |
| |
| │1382: movb $0x1,-0x270(%rbp) |
| |
| If use this, the number of branches jumping to that address can be printed as below. |
| Default is 'false'. |
| |
| │1 1382: movb $0x1,-0x270(%rbp) |
| |
| This option works with tui, stdio2 browsers. |
| |
| annotate.show_total_period:: |
| To compare two records on an instruction base, with this option |
| provided, display total number of samples that belong to a line |
| in assembly code. If this option is 'true', total periods are printed |
| instead of percent values as below. |
| |
| 302 │ mov %eax,%eax |
| |
| But if this option is 'false', percent values for overhead are printed i.e. |
| Default is 'false'. |
| |
| 99.93 │ mov %eax,%eax |
| |
| This option works with tui, stdio2, stdio browsers. |
| |
| annotate.show_nr_samples:: |
| By default perf annotate shows percentage of samples. This option |
| can be used to print absolute number of samples. Ex, when set as |
| false: |
| |
| Percent│ |
| 74.03 │ mov %fs:0x28,%rax |
| |
| When set as true: |
| |
| Samples│ |
| 6 │ mov %fs:0x28,%rax |
| |
| This option works with tui, stdio2, stdio browsers. |
| |
| annotate.offset_level:: |
| Default is '1', meaning just jump targets will have offsets show right beside |
| the instruction. When set to '2' 'call' instructions will also have its offsets |
| shown, 3 or higher will show offsets for all instructions. |
| |
| This option works with tui, stdio2 browsers. |
| |
| hist.*:: |
| hist.percentage:: |
| This option control the way to calculate overhead of filtered entries - |
| that means the value of this option is effective only if there's a |
| filter (by comm, dso or symbol name). Suppose a following example: |
| |
| Overhead Symbols |
| ........ ....... |
| 33.33% foo |
| 33.33% bar |
| 33.33% baz |
| |
| This is an original overhead and we'll filter out the first 'foo' |
| entry. The value of 'relative' would increase the overhead of 'bar' |
| and 'baz' to 50.00% for each, while 'absolute' would show their |
| current overhead (33.33%). |
| |
| ui.*:: |
| ui.show-headers:: |
| This option controls display of column headers (like 'Overhead' and 'Symbol') |
| in 'report' and 'top'. If this option is false, they are hidden. |
| This option is only applied to TUI. |
| |
| call-graph.*:: |
| The following controls the handling of call-graphs (obtained via the |
| -g/--call-graph options). |
| |
| call-graph.record-mode:: |
| The mode for user space can be 'fp' (frame pointer), 'dwarf' |
| and 'lbr'. The value 'dwarf' is effective only if libunwind |
| (or a recent version of libdw) is present on the system; |
| the value 'lbr' only works for certain cpus. The method for |
| kernel space is controlled not by this option but by the |
| kernel config (CONFIG_UNWINDER_*). |
| |
| call-graph.dump-size:: |
| The size of stack to dump in order to do post-unwinding. Default is 8192 (byte). |
| When using dwarf into record-mode, the default size will be used if omitted. |
| |
| call-graph.print-type:: |
| The print-types can be graph (graph absolute), fractal (graph relative), |
| flat and folded. This option controls a way to show overhead for each callchain |
| entry. Suppose a following example. |
| |
| Overhead Symbols |
| ........ ....... |
| 40.00% foo |
| | |
| ---foo |
| | |
| |--50.00%--bar |
| | main |
| | |
| --50.00%--baz |
| main |
| |
| This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly |
| half and half so 'fractal' shows 50.00% for each |
| (meaning that it assumes 100% total overhead of 'foo'). |
| |
| The 'graph' uses absolute overhead value of 'foo' as total so each of |
| 'bar' and 'baz' callchain will have 20.00% of overhead. |
| If 'flat' is used, single column and linear exposure of call chains. |
| 'folded' mean call chains are displayed in a line, separated by semicolons. |
| |
| call-graph.order:: |
| This option controls print order of callchains. The default is |
| 'callee' which means callee is printed at top and then followed by its |
| caller and so on. The 'caller' prints it in reverse order. |
| |
| If this option is not set and report.children or top.children is |
| set to true (or the equivalent command line option is given), |
| the default value of this option is changed to 'caller' for the |
| execution of 'perf report' or 'perf top'. Other commands will |
| still default to 'callee'. |
| |
| call-graph.sort-key:: |
| The callchains are merged if they contain same information. |
| The sort-key option determines a way to compare the callchains. |
| A value of 'sort-key' can be 'function' or 'address'. |
| The default is 'function'. |
| |
| call-graph.threshold:: |
| When there're many callchains it'd print tons of lines. So perf omits |
| small callchains under a certain overhead (threshold) and this option |
| control the threshold. Default is 0.5 (%). The overhead is calculated |
| by value depends on call-graph.print-type. |
| |
| call-graph.print-limit:: |
| This is a maximum number of lines of callchain printed for a single |
| histogram entry. Default is 0 which means no limitation. |
| |
| report.*:: |
| report.sort_order:: |
| Allows changing the default sort order from "comm,dso,symbol" to |
| some other default, for instance "sym,dso" may be more fitting for |
| kernel developers. |
| report.percent-limit:: |
| This one is mostly the same as call-graph.threshold but works for |
| histogram entries. Entries having an overhead lower than this |
| percentage will not be printed. Default is '0'. If percent-limit |
| is '10', only entries which have more than 10% of overhead will be |
| printed. |
| |
| report.queue-size:: |
| This option sets up the maximum allocation size of the internal |
| event queue for ordering events. Default is 0, meaning no limit. |
| |
| report.children:: |
| 'Children' means functions called from another function. |
| If this option is true, 'perf report' cumulates callchains of children |
| and show (accumulated) total overhead as well as 'Self' overhead. |
| Please refer to the 'perf report' manual. The default is 'true'. |
| |
| report.group:: |
| This option is to show event group information together. |
| Example output with this turned on, notice that there is one column |
| per event in the group, ref-cycles and cycles: |
| |
| # group: {ref-cycles,cycles} |
| # ======== |
| # |
| # Samples: 7K of event 'anon group { ref-cycles, cycles }' |
| # Event count (approx.): 6876107743 |
| # |
| # Overhead Command Shared Object Symbol |
| # ................ ....... ................. ................... |
| # |
| 99.84% 99.76% noploop noploop [.] main |
| 0.07% 0.00% noploop ld-2.15.so [.] strcmp |
| 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del |
| |
| top.*:: |
| top.children:: |
| Same as 'report.children'. So if it is enabled, the output of 'top' |
| command will have 'Children' overhead column as well as 'Self' overhead |
| column by default. |
| The default is 'true'. |
| |
| top.call-graph:: |
| This is identical to 'call-graph.record-mode', except it is |
| applicable only for 'top' subcommand. This option ONLY setup |
| the unwind method. To enable 'perf top' to actually use it, |
| the command line option -g must be specified. |
| |
| man.*:: |
| man.viewer:: |
| This option can assign a tool to view manual pages when 'help' |
| subcommand was invoked. Supported tools are 'man', 'woman' |
| (with emacs client) and 'konqueror'. Default is 'man'. |
| |
| New man viewer tool can be also added using 'man.<tool>.cmd' |
| or use different path using 'man.<tool>.path' config option. |
| |
| pager.*:: |
| pager.<subcommand>:: |
| When the subcommand is run on stdio, determine whether it uses |
| pager or not based on this value. Default is 'unspecified'. |
| |
| kmem.*:: |
| kmem.default:: |
| This option decides which allocator is to be analyzed if neither |
| '--slab' nor '--page' option is used. Default is 'slab'. |
| |
| record.*:: |
| record.build-id:: |
| This option can be 'cache', 'no-cache' or 'skip'. |
| 'cache' is to post-process data and save/update the binaries into |
| the build-id cache (in ~/.debug). This is the default. |
| But if this option is 'no-cache', it will not update the build-id cache. |
| 'skip' skips post-processing and does not update the cache. |
| |
| record.call-graph:: |
| This is identical to 'call-graph.record-mode', except it is |
| applicable only for 'record' subcommand. This option ONLY setup |
| the unwind method. To enable 'perf record' to actually use it, |
| the command line option -g must be specified. |
| |
| record.aio:: |
| Use 'n' control blocks in asynchronous (Posix AIO) trace writing |
| mode ('n' default: 1, max: 4). |
| |
| diff.*:: |
| diff.order:: |
| This option sets the number of columns to sort the result. |
| The default is 0, which means sorting by baseline. |
| Setting it to 1 will sort the result by delta (or other |
| compute method selected). |
| |
| diff.compute:: |
| This options sets the method for computing the diff result. |
| Possible values are 'delta', 'delta-abs', 'ratio' and |
| 'wdiff'. Default is 'delta'. |
| |
| trace.*:: |
| trace.add_events:: |
| Allows adding a set of events to add to the ones specified |
| by the user, or use as a default one if none was specified. |
| The initial use case is to add augmented_raw_syscalls.o to |
| activate the 'perf trace' logic that looks for syscall |
| pointer contents after the normal tracepoint payload. |
| |
| trace.args_alignment:: |
| Number of columns to align the argument list, default is 70, |
| use 40 for the strace default, zero to no alignment. |
| |
| trace.no_inherit:: |
| Do not follow children threads. |
| |
| trace.show_arg_names:: |
| Should syscall argument names be printed? If not then trace.show_zeros |
| will be set. |
| |
| trace.show_duration:: |
| Show syscall duration. |
| |
| trace.show_prefix:: |
| If set to 'yes' will show common string prefixes in tables. The default |
| is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED". |
| |
| trace.show_timestamp:: |
| Show syscall start timestamp. |
| |
| trace.show_zeros:: |
| Do not suppress syscall arguments that are equal to zero. |
| |
| trace.tracepoint_beautifiers:: |
| Use "libtraceevent" to use that library to augment the tracepoint arguments, |
| "libbeauty", the default, to use the same argument beautifiers used in the |
| strace-like sys_enter+sys_exit lines. |
| |
| ftrace.*:: |
| ftrace.tracer:: |
| Can be used to select the default tracer when neither -G nor |
| -F option is not specified. Possible values are 'function' and |
| 'function_graph'. |
| |
| llvm.*:: |
| llvm.clang-path:: |
| Path to clang. If omit, search it from $PATH. |
| |
| llvm.clang-bpf-cmd-template:: |
| Cmdline template. Below lines show its default value. Environment |
| variable is used to pass options. |
| "$CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS "\ |
| "-DLINUX_VERSION_CODE=$LINUX_VERSION_CODE " \ |
| "$CLANG_OPTIONS $PERF_BPF_INC_OPTIONS $KERNEL_INC_OPTIONS " \ |
| "-Wno-unused-value -Wno-pointer-sign " \ |
| "-working-directory $WORKING_DIR " \ |
| "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -O2 -o - $LLVM_OPTIONS_PIPE" |
| |
| llvm.clang-opt:: |
| Options passed to clang. |
| |
| llvm.kbuild-dir:: |
| kbuild directory. If not set, use /lib/modules/`uname -r`/build. |
| If set to "" deliberately, skip kernel header auto-detector. |
| |
| llvm.kbuild-opts:: |
| Options passed to 'make' when detecting kernel header options. |
| |
| llvm.dump-obj:: |
| Enable perf dump BPF object files compiled by LLVM. |
| |
| llvm.opts:: |
| Options passed to llc. |
| |
| samples.*:: |
| |
| samples.context:: |
| Define how many ns worth of time to show |
| around samples in perf report sample context browser. |
| |
| scripts.*:: |
| |
| Any option defines a script that is added to the scripts menu |
| in the interactive perf browser and whose output is displayed. |
| The name of the option is the name, the value is a script command line. |
| The script gets the same options passed as a full perf script, |
| in particular -i perfdata file, --cpu, --tid |
| |
| convert.*:: |
| |
| convert.queue-size:: |
| Limit the size of ordered_events queue, so we could control |
| allocation size of perf data files without proper finished |
| round events. |
| stat.*:: |
| |
| stat.big-num:: |
| (boolean) Change the default for "--big-num". To make |
| "--no-big-num" the default, set "stat.big-num=false". |
| |
| intel-pt.*:: |
| |
| intel-pt.cache-divisor:: |
| |
| intel-pt.mispred-all:: |
| If set, Intel PT decoder will set the mispred flag on all |
| branches. |
| |
| auxtrace.*:: |
| |
| auxtrace.dumpdir:: |
| s390 only. The directory to save the auxiliary trace buffer |
| can be changed using this option. Ex, auxtrace.dumpdir=/tmp. |
| If the directory does not exist or has the wrong file type, |
| the current directory is used. |
| |
| SEE ALSO |
| -------- |
| linkperf:perf[1] |