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+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.
+
+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 $HOME/.perfconfig like this:
+
+#
+# This is the config file, and
+# a '#' and ';' character indicates a comment
+#
+
+ [colors]
+ # Color variables
+ top = red, default
+ medium = green, default
+ normal = lightgray, default
+ selected = white, lightgray
+ jump_arrows = blue, default
+ addr = magenta, default
+ root = white, blue
+
+ [tui]
+ # Defaults if linked with libslang
+ report = on
+ annotate = on
+ top = on
+
+ [buildid]
+ # Default, disable using /dev/null
+ dir = ~/.debug
+
+ [annotate]
+ # Defaults
+ hide_src_code = false
+ use_offset = true
+ jump_arrows = true
+ show_nr_jumps = false
+
+ [help]
+ # Format can be man, info, web or html
+ format = man
+ autocorrect = 0
+
+ [ui]
+ show-headers = true
+
+ [call-graph]
+ # fp (framepointer), dwarf
+ record-mode = fp
+ print-type = graph
+ order = caller
+ sort-key = function
+
+ [report]
+ # Defaults
+ sort_order = comm,dso,symbol
+ percent-limit = 0
+ queue-size = 0
+ children = true
+ group = true
+
+You can hide source code of annotate feature setting the config to false with
+
+ % perf config annotate.hide_src_code=true
+
+If you want to add or modify several config items, you can do like
+
+ % perf config ui.show-headers=false kmem.default=slab
+
+To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do
+
+ % perf config --user report sort-order=srcline
+
+To change colors of selected line to other foreground and background colors
+in system config file (i.e. `$(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'.
+
+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 options work only for TUI.
+ 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;
+
+ 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
+
+ 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
+
+ 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++;
+ │ }
+
+ 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)
+
+ 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
+
+ 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.
+
+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.*::
+ When sub-commands 'top' and 'report' work with -g/—-children
+ there're options in control of call-graph.
+
+ call-graph.record-mode::
+ The record-mode can be 'fp' (frame pointer), 'dwarf' and 'lbr'.
+ The value of 'dwarf' is effective only if perf detect needed library
+ (libunwind or a recent version of libdw).
+ 'lbr' only work for cpus that support it.
+
+ 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'.
+
+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.
+
+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'.
+
+SEE ALSO
+--------
+linkperf:perf[1]
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