Flags


  <title>Clinic.js Flame</title> - v{{version}}

  <code>clinic flame</code> helps you find synchronous bottlenecks
  by creating a flamegraph visualization that assists in identifying
  function calls that may be blocking the event loop.

  For more information see the 0x readme, https://github.com/davidmarkclements/0x

  To run <code>clinic flame</code>

    <code>clinic flame -- node server.js</code>

  Once you exit (Ctrl-C) the process, your report will open in a browser window. You can disable this behavior:

    <code>clinic flame --open=false -- node server.js</code>

  If profiling on a server, it can be useful to only do data collection:

    <code>clinic flame --collect-only -- node server.js</code>

  You can then transfer the data and visualize it locally:

    <code>clinic flame --visualize-only PID.clinic.flame</code>

  You can use the --autocannon flag to simulate load on your server.
  --autocannon accepts configuration for autocannon using "subarg" syntax:

    <code>clinic flame --autocannon [ -m POST /api/example ] -- node server.js</code>

  When configuring --autocannon, the $PORT environment variable contains the
  port your server is listening on:

    <code>clinic flame --autocannon [ -m POST 'http://localhost:$PORT/?\$page=1' ] -- node server.js</code>

  Note that dollar signs ($) appearing in the URL must be escaped, else they
  will be treated as environment variables as well.

  You can profile the application using kernel tracing. This will capture native stack frames (C++ modules and Libuv I/O)

    <code>clinic flame --kernel-tracing -- node server.js</code>

  <h1>Flags</h1>
  -h | --help                Display Help
  -v | --version             Display Version
  --collect-only             Do not process data on termination
  --visualize-only datapath  Build or rebuild visualization from data
  --on-port                  Run a script when the server starts listening on a port.
  --autocannon               Run the autocannon benchmarking tool when the server starts listening on a port.
  --open                     Boolean to enable or disable your report opening in your web browser.
  --dest                     Destination for the collected data (default <code>.clinic/</code>).
  --kernel-tracing            Profile application using linux_perf (linux only).
  --stop-delay               Add a delay to close the process when a job is done through either `autocannon` or `on-port` flag (milliseconds)
  --name                     The --name flag sets a name for the output data, allowing you to replace existing reports without generating new ones. Example: <code>.clinic/node-19-test.clinic-flame</code>