onis

(pronounced onis)

Onis gives you introspection into object counts of live running ruby process.

Install

$ sudo gem install onis

Example

$ cd onis/

$ cat test/stringpwnd.rb
require 'onis'
puts Process.pid
a = []
while true ; a << "foo" ; sleep(0.5) ; end

$ ruby test/stringpwd.rb &
[1] 26584

$ onis
PID        COMMAND
------------------------------------------------------------
26584      ruby -I lib/ test/stringpwnd.rb

$ onis -f 26584
Class                                         Count
--------------------------------------------------------
String                                        3483
Class                                         156
Array                                         55
Module                                        25
Regexp                                        9
File                                          8
Hash                                          7
Float                                         6
Object                                        3
...

Color!

$ onis -f -c 26584

Watch!

$ onis -w 26584

How it works

1. Onis drops a tempfile named after the pid onis.<pid>
2. Onis then traps SIGUSR1
3. When SIGUSR1 is sent to a process that has required Onis, Onis will dump the ObjectSpace and counts to that tempfile.

TODO:

• handle fork

Thanks

• Aman Gupta (tmm1) for inspiration and example
• Ryan Tomayko for playing that great music at Columbus Cafe and telling me to take this one step further

License

Copyright (c) 2009 Blake Mizerany

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.