perf-top(1)
===========

NAME
----
perf-top - System profiling tool.

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

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


OPTIONS
-------
-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.

-g::
--group::
        Put the counters into a counter group.

-F <freq>::
--freq=<freq>::
	Profile at this frequency.

-i::
--inherit::
	Child tasks inherit counters, only makes sens with -p option.

-k <path>::
--vmlinux=<path>::
	Path to vmlinux.  Required for annotation functionality.

-m <pages>::
--mmap-pages=<pages>::
	Number of mmapped data pages.

-p <pid>::
--pid=<pid>::
	Profile events on existing Process ID.

-t <tid>::
--tid=<tid>::
        Profile events on existing thread ID.

-r <priority>::
--realtime=<priority>::
	Collect data with this RT SCHED_FIFO priority.

-s <symbol>::
--sym-annotate=<symbol>::
        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

-n::
--show-nr-samples::
	Show a column with the number of samples.

--show-total-period::
	Show a column with the sum of periods.

--dsos::
	Only consider symbols in these dsos.

--comms::
	Only consider symbols in these comms.

--symbols::
	Only consider these symbols.

-M::
--disassembler-style=:: Set disassembler style for objdump.

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

--asm-raw::
	Show raw instruction encoding of assembly instructions.

-G [type,min,order]::
--call-graph::
        Display call chains using type, min percent threshold and order.
	type can be either:
	- flat: single column, linear exposure of call chains.
	- graph: use a graph tree, displaying absolute overhead rates.
	- fractal: like graph, but displays relative rates. Each branch of
		 the tree is considered as a new profiled object.

	order can be either:
	- callee: callee based call graph.
	- caller: inverted caller based call graph.

	Default: fractal,0.5,callee.

INTERACTIVE PROMPTING KEYS
--------------------------

[d]::
	Display refresh delay.

[e]::
	Number of entries to display.

[E]::
	Event to display when multiple counters are active.

[f]::
	Profile display filter (>= hit count).

[F]::
	Annotation display filter (>= % of total).

[s]::
	Annotate symbol.

[S]::
	Stop annotation, return to full profile display.

[z]::
	Toggle event count zeroing across display updates.

[qQ]::
	Quit.

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


SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-list[1]