Published 2022-05-03.
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Have you ever wanted to know what functions your Ruby program is calling?
rbspy can tell you!
rbspy lets you profile Ruby processes that are already running.
You give it a PID, and it starts profiling!
It’s a sampling profiler, which means it's low overhead and safe to run in production.
Installing
I downloaded rbspy-x86_64-musl.tar.gz.
The musl build is statically linked and should be compatible with most Linux systems.
More details here.
Shell
$ wget -O ~/Downloads/rbspy.tar.gz https://github.com/rbspy/rbspy/releases/download/v0.12.1/rbspy-x86_64-musl.tar.gz --2022-05-03 07:58:33-- https://github.com/rbspy/rbspy/releases/download/v0.12.1/rbspy-x86_64-musl.tar.gz Resolving github.com (github.com)... 140.82.112.4 Connecting to github.com (github.com)|140.82.112.4|:443... connected. HTTP request sent, awaiting response... 302 Found Location: https://objects.githubusercontent.com/github-production-release-asset-2e65be/58655757/f10942b5-592b-4ed6-8a62-d76776c4fdb3?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20220503%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20220503T115837Z&X-Amz-Expires=300&X-Amz-Signature=7e70c4443ddd4053d887244deaa01ac8c2033dbc06b9bdf9d4389580bebfa179&X-Amz-SignedHeaders=host&actor_id=0&key_id=0&repo_id=58655757&response-content-disposition=attachment%3B%20filename%3Drbspy-x86_64-musl.tar.gz&response-content-type=application%2Foctet-stream [following] --2022-05-03 07:58:33-- https://objects.githubusercontent.com/github-production-release-asset-2e65be/58655757/f10942b5-592b-4ed6-8a62-d76776c4fdb3?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20220503%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20220503T115837Z&X-Amz-Expires=300&X-Amz-Signature=7e70c4443ddd4053d887244deaa01ac8c2033dbc06b9bdf9d4389580bebfa179&X-Amz-SignedHeaders=host&actor_id=0&key_id=0&repo_id=58655757&response-content-disposition=attachment%3B%20filename%3Drbspy-x86_64-musl.tar.gz&response-content-type=application%2Foctet-stream Resolving objects.githubusercontent.com (objects.githubusercontent.com)... 185.199.109.133, 185.199.108.133, 185.199.110.133, ... Connecting to objects.githubusercontent.com (objects.githubusercontent.com)|185.199.109.133|:443... connected. HTTP request sent, awaiting response... 200 OK Length: 2610927 (2.5M) [application/octet-stream] Saving to: ‘/home/mslinn/Downloads/rbspy.tar.gz’ /home/mslinn/Downloads/rbspy.tar.gz 100%[===========================================================================================>] 2.49M --.-KB/s in 0.04s 2022-05-03 07:58:34 (57.7 MB/s) - ‘/home/mslinn/Downloads/rbspy.tar.gz’ saved [2610927/2610927]
The recommended directory for user scripts on Ubuntu is ~/.local/bin/.
This directory does not exist by default.
More information here.
Shell
$ cd ~/.local/bin/ $ tar -xvf ~/Downloads/rbspy.tar.gz rbspy-x86_64-musl $ mv ./rbspy-x86_64-musl rbspy $ chmod a+x rbspy
Now we can learn how to use rbspy:
Shell
$ rbspy --help
Sampling profiler for Ruby programs
USAGE:
rbspy <SUBCOMMAND>
OPTIONS:
-h, --help Print help information
-V, --version Print version information
SUBCOMMANDS:
help Print this message or the help of the given subcommand(s)
record Continuously capture traces from a Ruby process
report Generate visualization from raw data recorded by `rbspy record`
snapshot Capture a single stack trace from a running Ruby program