---
name: "perf_3.2-top"
section: "1"
platform: "linux"
package: "linux-tools-3.2"
version: "3.2.17-1"
release: "Debian 7 (Wheezy)"
platforms: ["linux"]
url: "https://new.carta.tech/perf_3.2-top"
---

# perf\_3.2-top(1)

System profiling tool.

## NAME

perf-top - System profiling tool.

## SYNOPSIS

```
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

[**perf\_3.2-stat**(1)](/perf_3.2-stat/1.md), [**perf\_3.2-list**(1)](/perf_3.2-list/1.md)