perf-top(1) System profiling tool.


perf top [-e <EVENT> | --event=EVENT] [<options>]


This command generates and displays a performance counter profile in real time.


-a, --all-cpus

System-wide collection. (default)

-c <count>, --count=<count>

Event period to sample.

-C <cpu-list>, --cpu=<cpu>

Monitor only on 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 monitor all CPUS.

-d <seconds>, --delay=<seconds>

Number of seconds to delay between refreshes.

-e <event>, --event=<event>

Select the PMU event. Selection can be a symbolic event name (use perf list to list all events) or a raw PMU event (eventsel+umask) in the form of rNNN where NNN is a hexadecimal event descriptor.

-E <entries>, --entries=<entries>

Display this many functions.

-f <count>, --count-filter=<count>

Only display functions with more events than this.


Put the counters into a counter group.

-F <freq>, --freq=<freq>

Profile at this frequency.

-i, --inherit

Child tasks do not inherit counters.

-k <path>, --vmlinux=<path>

Path to vmlinux. Required for annotation functionality.

-m <pages>, --mmap-pages=<pages>

Number of mmap data pages (must be a power of two) or size specification with appended unit character - B/K/M/G. The size is rounded up to have nearest pages power of two value.

-p <pid>, --pid=<pid>

Profile events on existing Process ID (comma separated list).

-t <tid>, --tid=<tid>

Profile events on existing thread ID (comma separated list).

-u, --uid=

Record events in threads owned by uid. Name or number.

-r <priority>, --realtime=<priority>

Collect data with this RT SCHED_FIFO priority.


Annotate this symbol.

-K, --hide_kernel_symbols

Hide kernel symbols.

-U, --hide_user_symbols

Hide user symbols.

-D, --dump-symtab

Dump the symbol table used for profiling.

-v, --verbose

Be more verbose (show counter open errors, etc).

-z, --zero

Zero history across display updates.

-s, --sort

Sort by key(s): pid, comm, dso, symbol, parent, srcline, weight, local_weight, abort, in_tx, transaction, overhead, sample, period. Please see description of --sort in the perf-report man page.


Specify output field - multiple keys can be specified in CSV format. Following fields are available: overhead, overhead_sys, overhead_us, overhead_children, sample and period. Also it can contain any sort key(s).

By default, every sort keys not specified in --field will be appended

-n, --show-nr-samples

Show a column with the number of samples.


Show a column with the sum of periods.


Only consider symbols in these dsos. This option will affect the percentage of the overhead column. See --percentage for more info.


Only consider symbols in these comms. This option will affect the percentage of the overhead column. See --percentage for more info.


Only consider these symbols. This option will affect the percentage of the overhead column. See --percentage for more info.

-M, --disassembler-style=

Set disassembler style for objdump.


Interleave source code with assembly code. Enabled by default, disable with --no-source.


Show raw instruction encoding of assembly instructions.


Enables call-graph (stack chain/backtrace) recording.


Setup and enable call-graph (stack chain/backtrace) recording, implies -g.


Accumulate callchain of children to parent entry so that then can show up in the output. The output will have a new "Children" column and will be sorted on the data. It requires -g/--call-graph option enabled.


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.

Default: 127


Ignore callees of the function(s) matching the given regex. This has the effect of collecting the callers of each such function into one place in the call-graph tree.


Do not show entries which have an overhead under that percent. (Default: 0).


Determine how to display the overhead percentage of filtered entries. Filters can be applied by --comms, --dsos and/or --symbols options and Zoom operations on the TUI (thread, dso, etc).

"relative" means it's relative to filtered entries only so that the
sum of shown entries will be always 100%. "absolute" means it retains
the original value before and after the filter is applied.



Display refresh delay.


Number of entries to display.


Event to display when multiple counters are active.


Profile display filter (>= hit count).


Annotation display filter (>= % of total).


Annotate symbol.


Stop annotation, return to full profile display.


Toggle event count zeroing across display updates.



Pressing any unmapped key displays a menu, and prompts for input.