pflames

pflames is a tool for generating
flamegraphs from various profile
formats.

The following formats are supported (detected by file extension):

.cpuprofile, as generated by older Chrome DevTools,
v8-profiler,
cli-profile, etc.
* perf.data, as generated by perf record on Linux.
isolate.log, as generated by node --prof.

The data is processed from these formats into flamegraphs generated by Brendan
Gregg's FlameGraph tool, saved to
a local file based on the input filename, then immediately opened in your web
browser.

Usage

Examples:

``
$ npm i -g cli-profile
$ cli-profile myscript.js
$ ls *.cpuprofile
profile1522910623600.cpuprofile
$ pflames profile1522910623600.cpuprofile
`

`
$ # Note: Ensure your script has process.on('SIGINT', process.exit)
$ node --prof myscript.js
$ ls *.log
isolate-0x2259700-v8.log
$ pflames isolate-0x2259700-v8.log
`

`
$ sudo perf record -i -g -F 99 -- node --perf-basic-prof myscript.js
$ pflames perf.data
`

You can also compare two profiles of the same format by passing them both in. A
difference flamegraph will be generated:

`
$ pflames thing1.cpuprofile thing2.cpuprofile
`

You can also use the same data to generate an icicle graph, so you can get a
better view of what's calling a heavy function:

`
$ pflames --icicle thing1.cpuprofile
`

$3

You can use the run and attach commands to profile Node.js and other Linux
processes. This will run perf record behind the scenese to generate a
perf.data.

* run spawns a process with the given command with perf record, profiling
it for its entire lifetime. If the process binary being run is node, it will
add --perf-basic-prof to the options. Examples:

`


profile a Node.js app

$ pflames run node myapp.js

profile a Rust app (you should use release builds for this)

$ pflames run target/release/myapp
`

* attach starts profiling a given PID until the that process exits, a
SIGINT (Ctrl+C) is received, or a given number of seconds has elapsed.

`


Assume PID 1234 is running and we want to profile it:

$ pflames attach 1234

Now either Ctrl+C to finish profiling or wait for 1234 to finish

Or profile it for exactly 5 seconds:

$ pflames attach 1234 5
`

Both of these commands produce perf.data files which can be then processed
with plfames:

`
$ pflames perf.data
``

License

MIT License. See LICENSE.txt