perf-script(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COLOPHON

PERF-SCRIPT(1)                 perf Manual                PERF-SCRIPT(1)

NAME         top

       perf-script - Read perf.data (created by perf record) and display
       trace output

SYNOPSIS         top

       perf script [<options>]
       perf script [<options>] record <script> [<record-options>] <command>
       perf script [<options>] report <script> [script-args]
       perf script [<options>] <script> <required-script-args> [<record-options>] <command>
       perf script [<options>] <top-script> [script-args]

DESCRIPTION         top

       This command reads the input file and displays the trace
       recorded.

       There are several variants of perf script:

           'perf script' to see a detailed trace of the workload that was
           recorded.

           You can also run a set of pre-canned scripts that aggregate and
           summarize the raw trace data in various ways (the list of scripts is
           available via 'perf script -l').  The following variants allow you to
           record and run those scripts:

           'perf script record <script> <command>' to record the events required
           for 'perf script report'.  <script> is the name displayed in the
           output of 'perf script --list' i.e. the actual script name minus any
           language extension.  If <command> is not specified, the events are
           recorded using the -a (system-wide) 'perf record' option.

           'perf script report <script> [args]' to run and display the results
           of <script>.  <script> is the name displayed in the output of 'perf
           script --list' i.e. the actual script name minus any language
           extension.  The perf.data output from a previous run of 'perf script
           record <script>' is used and should be present for this command to
           succeed.  [args] refers to the (mainly optional) args expected by
           the script.

           'perf script <script> <required-script-args> <command>' to both
           record the events required for <script> and to run the <script>
           using 'live-mode' i.e. without writing anything to disk.  <script>
           is the name displayed in the output of 'perf script --list' i.e. the
           actual script name minus any language extension.  If <command> is
           not specified, the events are recorded using the -a (system-wide)
           'perf record' option.  If <script> has any required args, they
           should be specified before <command>.  This mode doesn't allow for
           optional script args to be specified; if optional script args are
           desired, they can be specified using separate 'perf script record'
           and 'perf script report' commands, with the stdout of the record step
           piped to the stdin of the report script, using the '-o -' and '-i -'
           options of the corresponding commands.

           'perf script <top-script>' to both record the events required for
           <top-script> and to run the <top-script> using 'live-mode'
           i.e. without writing anything to disk.  <top-script> is the name
           displayed in the output of 'perf script --list' i.e. the actual
           script name minus any language extension; a <top-script> is defined
           as any script name ending with the string 'top'.

           [<record-options>] can be passed to the record steps of 'perf script
           record' and 'live-mode' variants; this isn't possible however for
           <top-script> 'live-mode' or 'perf script report' variants.

           See the 'SEE ALSO' section for links to language-specific
           information on how to write and run your own trace scripts.

OPTIONS         top

       <command>...
           Any command you can specify in a shell.

       -D, --dump-raw-trace=
           Display verbose dump of the trace data.

       --dump-unsorted-raw-trace=
           Same as --dump-raw-trace but not sorted in time order.

       -L, --Latency=
           Show latency attributes (irqs/preemption disabled, etc).

       -l, --list=
           Display a list of available trace scripts.

       -s [lang], --script=
           Process trace data with the given script
           ([lang]:script[.ext]). If the string lang is specified in
           place of a script name, a list of supported languages will be
           displayed instead.

       -g, --gen-script=
           Generate perf-script.[ext] starter script for given language,
           using current perf.data.

       --dlfilter=<file>
           Filter sample events using the given shared object file.
           Refer perf-dlfilter(1)

       --dlarg=<arg>
           Pass arg as an argument to the dlfilter. --dlarg may be
           repeated to add more arguments.

       --list-dlfilters
           Display a list of available dlfilters. Use with option -v
           (must come before option --list-dlfilters) to show long
           descriptions.

       -a
           Force system-wide collection. Scripts run without a <command>
           normally use -a by default, while scripts run with a
           <command> normally don’t - this option allows the latter to
           be run in system-wide mode.

       -i, --input=
           Input file name. (default: perf.data unless stdin is a fifo)

       -d, --debug-mode
           Do various checks like samples ordering and lost events.

       -F, --fields
           Comma separated list of fields to print. Options are: comm,
           tid, pid, time, cpu, event, trace, ip, sym, dso, dsoff, addr,
           symoff, srcline, period, iregs, uregs, brstack, brstacksym,
           flags, bpf-output, brstackinsn, brstackinsnlen,
           brstackdisasm, brstackoff, callindent, insn, disasm, insnlen,
           synth, phys_addr, metric, misc, srccode, ipc, data_page_size,
           code_page_size, ins_lat, machine_pid, vcpu, cgroup,
           retire_lat,

               Field list can be prepended with the type, trace, sw or hw,
               to indicate to which event type the field list applies.
               e.g., -F sw:comm,tid,time,ip,sym  and -F trace:time,cpu,trace

               perf script -F <fields>

               is equivalent to:

               perf script -F trace:<fields> -F sw:<fields> -F hw:<fields>

               i.e., the specified fields apply to all event types if the type string
               is not given.

               In addition to overriding fields, it is also possible to add or remove
               fields from the defaults. For example

               -F -cpu,+insn

               removes the cpu field and adds the insn field. Adding/removing fields
               cannot be mixed with normal overriding.

               The arguments are processed in the order received. A later usage can
               reset a prior request. e.g.:

               -F trace: -F comm,tid,time,ip,sym

               The first -F suppresses trace events (field list is ""), but then the
               second invocation sets the fields to comm,tid,time,ip,sym. In this case a
               warning is given to the user:

               "Overriding previous field request for all events."

               Alternatively, consider the order:

               -F comm,tid,time,ip,sym -F trace:

               The first -F sets the fields for all events and the second -F
               suppresses trace events. The user is given a warning message about
               the override, and the result of the above is that only S/W and H/W
               events are displayed with the given fields.

               It's possible tp add/remove fields only for specific event type:

               -Fsw:-cpu,-period

               removes cpu and period from software events.

               For the 'wildcard' option if a user selected field is invalid for an
               event type, a message is displayed to the user that the option is
               ignored for that type. For example:

               $ perf script -F comm,tid,trace
               'trace' not valid for hardware events. Ignoring.
               'trace' not valid for software events. Ignoring.

               Alternatively, if the type is given an invalid field is specified it
               is an error. For example:

               perf script -v -F sw:comm,tid,trace
               'trace' not valid for software events.

               At this point usage is displayed, and perf-script exits.

               The flags field is synthesized and may have a value when Instruction
               Trace decoding. The flags are "bcrosyiABExghDt" which stand for branch,
               call, return, conditional, system, asynchronous, interrupt,
               transaction abort, trace begin, trace end, in transaction, VM-Entry,
               VM-Exit, interrupt disabled and interrupt disable toggle respectively.
               Known combinations of flags are printed more nicely e.g.
               "call" for "bc", "return" for "br", "jcc" for "bo", "jmp" for "b",
               "int" for "bci", "iret" for "bri", "syscall" for "bcs", "sysret" for "brs",
               "async" for "by", "hw int" for "bcyi", "tx abrt" for "bA", "tr strt" for "bB",
               "tr end" for "bE", "vmentry" for "bcg", "vmexit" for "bch".
               However the "x", "D" and "t" flags will be displayed separately in those
               cases e.g. "jcc     (xD)" for a condition branch within a transaction
               with interrupts disabled. Note, interrupts becoming disabled is "t",
               whereas interrupts becoming enabled is "Dt".

               The callindent field is synthesized and may have a value when
               Instruction Trace decoding. For calls and returns, it will display the
               name of the symbol indented with spaces to reflect the stack depth.

               When doing instruction trace decoding, insn, disasm and insnlen give the
               instruction bytes, disassembled instructions (requires libcapstone support)
               and the instruction length of the current instruction respectively.

               The synth field is used by synthesized events which may be created when
               Instruction Trace decoding.

               The ipc (instructions per cycle) field is synthesized and may have a value when
               Instruction Trace decoding.

               The machine_pid and vcpu fields are derived from data resulting from using
               perf inject to insert a perf.data file recorded inside a virtual machine into
               a perf.data file recorded on the host at the same time.

               The cgroup fields requires sample having the cgroup id which is saved
               when "--all-cgroups" option is passed to 'perf record'.

               Finally, a user may not set fields to none for all event types.
               i.e., -F "" is not allowed.

               The brstack output includes branch related information with raw addresses using the
               /v/v/v/v/cycles syntax in the following order:
               FROM: branch source instruction
               TO  : branch target instruction
               M/P/-: M=branch target mispredicted or branch direction was mispredicted, P=target predicted or direction predicted, -=not supported
               X/- : X=branch inside a transactional region, -=not in transaction region or not supported
               A/- : A=TSX abort entry, -=not aborted region or not supported
               cycles

               The brstacksym is identical to brstack, except that the FROM and TO addresses are printed in a symbolic form if possible.

               When brstackinsn is specified the full assembler sequences of branch sequences for each sample
               is printed. This is the full execution path leading to the sample. This is only supported when the
               sample was recorded with perf record -b or -j any.

               Use brstackinsnlen to print the brstackinsn lenght. For example, you
               can’t know the next sequential instruction after an unconditional branch unless
               you calculate that based on its length.

               brstackdisasm acts like brstackinsn, but will print disassembled instructions if
               perf is built with the capstone library.

               The brstackoff field will print an offset into a specific dso/binary.

               With the metric option perf script can compute metrics for
               sampling periods, similar to perf stat. This requires
               specifying a group with multiple events defining metrics with the :S option
               for perf record. perf will sample on the first event, and
               print computed metrics for all the events in the group. Please note
               that the metric computed is averaged over the whole sampling
               period (since the last sample), not just for the sample point.

               For sample events it's possible to display misc field with -F +misc option,
               following letters are displayed for each bit:

               PERF_RECORD_MISC_KERNEL               K
               PERF_RECORD_MISC_USER                 U
               PERF_RECORD_MISC_HYPERVISOR           H
               PERF_RECORD_MISC_GUEST_KERNEL         G
               PERF_RECORD_MISC_GUEST_USER           g
               PERF_RECORD_MISC_MMAP_DATA*           M
               PERF_RECORD_MISC_COMM_EXEC            E
               PERF_RECORD_MISC_SWITCH_OUT           S
               PERF_RECORD_MISC_SWITCH_OUT_PREEMPT   Sp

               $ perf script -F +misc ...
                sched-messaging  1414 K     28690.636582:       4590 cycles ...
                sched-messaging  1407 U     28690.636600:     325620 cycles ...
                sched-messaging  1414 K     28690.636608:      19473 cycles ...
               misc field ___________/

       -k, --vmlinux=<file>
           vmlinux pathname

       --kallsyms=<file>
           kallsyms pathname

       --symfs=<directory>
           Look for files with symbols relative to this directory.

       -G, --hide-call-graph
           When printing symbols do not display call chain.

       --stop-bt
           Stop display of callgraph at these symbols

       -C, --cpu
           Only report samples for the list of CPUs provided. Multiple
           CPUs can be provided as a comma-separated list with no space:
           0,1. Ranges of CPUs are specified with -: 0-2. Default is to
           report samples on all CPUs.

       -c, --comms=
           Only display events for these comms. CSV that understands
           file://filename entries.

       --pid=
           Only show events for given process ID (comma separated list).

       --tid=
           Only show events for given thread ID (comma separated list).

       -I, --show-info
           Display extended information about the perf.data file. This
           adds information which may be very large and thus may clutter
           the display. It currently includes: cpu and numa topology of
           the host system. It can only be used with the perf script
           report mode.

       --show-kernel-path
           Try to resolve the path of [kernel.kallsyms]

       --show-task-events Display task related events (e.g. FORK, COMM,
       EXIT).

       --show-mmap-events Display mmap related events (e.g. MMAP,
       MMAP2).

       --show-namespace-events Display namespace events i.e. events of
       type PERF_RECORD_NAMESPACES.

       --show-switch-events Display context switch events i.e. events of
       type PERF_RECORD_SWITCH or PERF_RECORD_SWITCH_CPU_WIDE.

       --show-lost-events Display lost events i.e. events of type
       PERF_RECORD_LOST.

       --show-round-events Display finished round events i.e. events of
       type PERF_RECORD_FINISHED_ROUND.

       --show-bpf-events Display bpf events i.e. events of type
       PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT.

       --show-cgroup-events Display cgroup events i.e. events of type
       PERF_RECORD_CGROUP.

       --show-text-poke-events Display text poke events i.e. events of
       type PERF_RECORD_TEXT_POKE and PERF_RECORD_KSYMBOL.

       --demangle
           Demangle symbol names to human readable form. It’s enabled by
           default, disable with --no-demangle.

       --demangle-kernel
           Demangle kernel symbol names to human readable form (for C++
           kernels).

       --header Show perf.data header.

       --header-only Show only perf.data header.

       --itrace
           Options for decoding instruction tracing data. The options
           are:

               i       synthesize instructions events
               y       synthesize cycles events
               b       synthesize branches events (branch misses for Arm SPE)
               c       synthesize branches events (calls only)
               r       synthesize branches events (returns only)
               x       synthesize transactions events
               w       synthesize ptwrite events
               p       synthesize power events (incl. PSB events for Intel PT)
               o       synthesize other events recorded due to the use
                       of aux-output (refer to perf record)
               I       synthesize interrupt or similar (asynchronous) events
                       (e.g. Intel PT Event Trace)
               e       synthesize error events
               d       create a debug log
               f       synthesize first level cache events
               m       synthesize last level cache events
               M       synthesize memory events
               t       synthesize TLB events
               a       synthesize remote access events
               g       synthesize a call chain (use with i or x)
               G       synthesize a call chain on existing event records
               l       synthesize last branch entries (use with i or x)
               L       synthesize last branch entries on existing event records
               s       skip initial number of events
               q       quicker (less detailed) decoding
               A       approximate IPC
               Z       prefer to ignore timestamps (so-called "timeless" decoding)
               T       use the timestamp trace as kernel time

               The default is all events i.e. the same as --itrace=iybxwpe,
               except for perf script where it is --itrace=ce

               In addition, the period (default 100000, except for perf script where it is 1)
               for instructions events can be specified in units of:

               i       instructions
               t       ticks
               ms      milliseconds
               us      microseconds
               ns      nanoseconds (default)

               Also the call chain size (default 16, max. 1024) for instructions or
               transactions events can be specified.

               Also the number of last branch entries (default 64, max. 1024) for
               instructions or transactions events can be specified.

               Similar to options g and l, size may also be specified for options G and L.
               On x86, note that G and L work poorly when data has been recorded with
               large PEBS. Refer linkperf:perf-intel-pt[1] man page for details.

               It is also possible to skip events generated (instructions, branches, transactions,
               ptwrite, power) at the beginning. This is useful to ignore initialization code.

               --itrace=i0nss1000000

               skips the first million instructions.

               The 'e' option may be followed by flags which affect what errors will or
               will not be reported. Each flag must be preceded by either '+' or '-'.
               The flags are:
                       o       overflow
                       l       trace data lost

               If supported, the 'd' option may be followed by flags which affect what
               debug messages will or will not be logged. Each flag must be preceded
               by either '+' or '-'. The flags are:
                       a       all perf events
                       e       output only on errors (size configurable - see linkperf:perf-config[1])
                       o       output to stdout

               If supported, the 'q' option may be repeated to increase the effect.

               To disable decoding entirely, use --no-itrace.

       --full-source-path
           Show the full path for source files for srcline output.

       --max-stack
           Set the stack depth limit when parsing the callchain,
           anything beyond the specified depth will be ignored. This is
           a trade-off between information loss and faster processing
           especially for workloads that can have a very long callchain
           stack. Note that when using the --itrace option the
           synthesized callchain size will override this value if the
           synthesized callchain size is bigger.

               Default: 127

       --ns
           Use 9 decimal places when displaying time (i.e. show the
           nanoseconds)

       -f, --force
           Don’t do ownership validation.

       --time
           Only analyze samples within given time window:
           <start>,<stop>. Times have the format seconds.nanoseconds. If
           start is not given (i.e. time string is ,x.y) then analysis
           starts at the beginning of the file. If stop time is not
           given (i.e. time string is x.y,) then analysis goes to end of
           file. Multiple ranges can be separated by spaces, which
           requires the argument to be quoted e.g. --time
           "1234.567,1234.789 1235,"

               Also support time percent with multiple time ranges. Time string is
               'a%/n,b%/m,...' or 'a%-b%,c%-%d,...'.

               For example:
               Select the second 10% time slice:
               perf script --time 10%/2

               Select from 0% to 10% time slice:
               perf script --time 0%-10%

               Select the first and second 10% time slices:
               perf script --time 10%/1,10%/2

               Select from 0% to 10% and 30% to 40% slices:
               perf script --time 0%-10%,30%-40%

       --max-blocks
           Set the maximum number of program blocks to print with
           brstackinsn for each sample.

       --reltime
           Print time stamps relative to trace start.

       --deltatime
           Print time stamps relative to previous event.

       --per-event-dump
           Create per event files with a "perf.data.EVENT.dump" name
           instead of printing to stdout, useful, for instance, for
           generating flamegraphs.

       --inline
           If a callgraph address belongs to an inlined function, the
           inline stack will be printed. Each entry has function name
           and file/line. Enabled by default, disable with --no-inline.

       --insn-trace[=<raw|disasm>]
           Show instruction stream in bytes (raw) or disassembled
           (disasm) for intel_pt traces. The default is raw. To use xed,
           combine raw with --xed to show disassembly done by xed.

       --xed
           Run xed disassembler on output. Requires installing the xed
           disassembler.

       -S, --symbols=symbol[,symbol...]
           Only consider the listed symbols. Symbols are typically a
           name but they may also be hexadecimal address.

               The hexadecimal address may be the start address of a symbol or
               any other address to filter the trace records

               For example, to select the symbol noploop or the address 0x4007a0:
               perf script --symbols=noploop,0x4007a0

               Support filtering trace records by symbol name, start address of
               symbol, any hexadecimal address and address range.

               The comparison order is:

            1. symbol name comparison

            2. symbol start address comparison.

            3. any hexadecimal address comparison.

            4. address range comparison (see --addr-range).

       --addr-range
           Use with -S or --symbols to list traced records within
           address range.

               For example, to list the traced records within the address range
               [0x4007a0, 0x0x4007a9]:
               perf script -S 0x4007a0 --addr-range 10

       --dsos=
           Only consider symbols in these DSOs.

       --call-trace
           Show call stream for intel_pt traces. The CPUs are
           interleaved, but can be filtered with -C.

       --call-ret-trace
           Show call and return stream for intel_pt traces.

       --graph-function
           For itrace only show specified functions and their callees
           for itrace. Multiple functions can be separated by comma.

       --switch-on EVENT_NAME
           Only consider events after this event is found.

       --switch-off EVENT_NAME
           Stop considering events after this event is found.

       --show-on-off-events
           Show the --switch-on/off events too.

       --stitch-lbr
           Show callgraph with stitched LBRs, which may have more
           complete callgraph. The perf.data file must have been
           obtained using perf record --call-graph lbr. Disabled by
           default. In common cases with call stack overflows, it can
           recreate better call stacks than the default lbr call stack
           output. But this approach is not foolproof. There can be
           cases where it creates incorrect call stacks from incorrect
           matches. The known limitations include exception handing such
           as setjmp/longjmp will have calls/returns not match.

       --guestmount=<path>
           Guest OS root file system mount directory. Users mount guest
           OS root directories under <path> by a specific filesystem
           access method, typically, sshfs. For example, start 2 guest
           OS, one’s pid is 8888 and the other’s is 9999:

               $ mkdir ~/guestmount
               $ cd ~/guestmount
               $ sshfs -o allow_other,direct_io -p 5551 localhost:/ 8888/
               $ sshfs -o allow_other,direct_io -p 5552 localhost:/ 9999/
               $ perf script --guestmount=~/guestmount

       --guestkallsyms=<path>
           Guest OS /proc/kallsyms file copy. perf reads it to get guest
           kernel symbols. Users copy it out from guest OS.

       --guestmodules=<path>
           Guest OS /proc/modules file copy. perf reads it to get guest
           kernel module information. Users copy it out from guest OS.

       --guestvmlinux=<path>
           Guest OS kernel vmlinux.

       --guest-code
           Indicate that guest code can be found in the hypervisor
           process, which is a common case for KVM test programs.

SEE ALSO         top

       perf-record(1), perf-script-perl(1), perf-script-python(1),
       perf-intel-pt(1), perf-dlfilter(1)

COLOPHON         top

       This page is part of the perf (Performance analysis tools for
       Linux (in Linux source tree)) project.  Information about the
       project can be found at 
       ⟨https://perf.wiki.kernel.org/index.php/Main_Page⟩.  If you have a
       bug report for this manual page, send it to
       [email protected].  This page was obtained from the
       project's upstream Git repository
       ⟨http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git⟩
       on 2024-06-14.  (At that time, the date of the most recent commit
       that was found in the repository was 2024-06-13.)  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
       the page, or you have corrections or improvements to the
       information in this COLOPHON (which is not part of the original
       manual page), send a mail to [email protected]

perf                           2024-04-05                 PERF-SCRIPT(1)

Pages that refer to this page: perf(1)perf-arm-spe(1)perf-config(1)perf-dlfilter(1)perf-intel-pt(1)perf-script-perl(1)perf-script-python(1)perf-trace(1)