---
name: "etop"
section: "3erl"
platform: "linux"
package: "erlang-manpages"
version: "1:25.2.3+dfsg-1+deb12u4"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/etop"
---

# etop(3erl)

Erlang Top is a tool for presenting information about Erlang processes similar to the information presented by "top" in UNIX.

## NAME

etop - Erlang Top is a tool for presenting information about Erlang\
   processes similar to the information presented by "top" in UNIX.

## DESCRIPTION

Start Erlang Top with the provided scripts *etop*. This starts a hidden Erlang node that connects to the node to be measured. The measured node is specified with option *-node*. If the measured node has a different cookie than the default cookie for the user who invokes the script, the cookie must be explicitly specified with option *-setcookie*.

Under Windows, batch file *etop.bat* can be used.

When executing the *etop* script, configuration parameters can be specified as command-line options, for example, *etop -node testnode@myhost -setcookie MyCookie*. The following configuration parameters exist for the tool:

- ***node*:**

  The measured node.

  Value: *atom()*

  Mandatory

- ***setcookie*:**

  Cookie to use for the *etop* node. Must be same as the cookie on the measured node.

  Value: *atom()*

- ***lines*:**

  Number of lines (processes) to display.

  Value: *integer()*

  Default: *10*

- ***interval*:**

  Time interval (in seconds) between each update of the display.

  Value: *integer()*

  Default: *5*

- ***accumulate*:**

  If *true*, the execution time and reductions are accumulated.

  Value: *boolean()*

  Default: *false*

- ***sort*:**

  Identifies what information to sort by.

  Value: *runtime \| reductions \| memory \| msg\_q*

  Default: *runtime* (*reductions* if *tracing=off*)

- ***tracing*:**

  *etop* uses the Erlang trace facility, and thus no other tracing is possible on the measured node while *etop* is running, unless this option is set to *off*. Also helpful if the *etop* tracing causes too high load on the measured node. With tracing off, runtime is not measured.

  Value: *on \| off*

  Default: *on*

For details about Erlang Top, see the User's Guide.

## EXPORTS

**start() -\> ok**\

Starts *etop*. Notice that *etop* is preferably started with the *etop* script.

**start(Options) -\> ok**\

Types:

Options = \[Option\]\
 Option = {Key, Value}\
 Key = atom()\
 Value = term()\

Starts *etop*. To view the possible options, use *help/0*.

**help() -\> ok**\

Displays the help of *etop* and its options.

**config(Key,Value) -\> Result**\

Types:

Result = ok \| {error,Reason}\
 Key = lines \| interval \| accumulate \| sort\
 Value = term()\

Changes the configuration parameters of the tool during runtime. Allowed parameters are *lines*, *interval*, *accumulate*, and *sort*.

**dump(File) -\> Result**\

Types:

Result = ok \| {error,Reason}\
 File = string()\

Dumps the current display to a text file.

**stop() -\> stop**\

Terminates *etop*.