Rails unresponsive when profiling an asset

[joallard]

My main (S)CSS file started taking up 30s to compile in development on every change, so I thought I'd try the gem.

When I called the firegraph on my application.css, the application goes completely moot. It does not finish the request, just leaves the request hanging. Only a SIGKILL will end the zombie.

Note it does not happen when (a) Sass hasn't changed, or (b) no firegraph is asked for.

Suggestions?