I moved my first VPS hosted slice over to phusion passenger (aka mod_rails) last night and was pleased so see the memory usage on my slice immediately drop about 15%. However, this morning I had lots of cryptic error messages about ruby_inline as follows:

Permission denied – /var/www/apps/mysite.org/releases/20080528201859/tmp/.ruby_inline/Inline_ImageScience_aa58.c
/usr/lib/ruby/gems/1.8/gems/RubyInline-3.6.7/lib/inline.rb:731:in `initialize’

I had already dealt with this issue when first setting up imagescience, and this looked related, but slightly different.

What I didn’t forsee was that previously, my mongrels were started with sudo – therefore running as root. When running with passenger, the user www-data was now the one that needed write access to the tmp directory, where rubyinline is doing its thing.

A quick permission change, then a restart with touch tmp/restart.txt and everything was green.

Overall, I’m really happy with the ease of setup and performance of passenger so far.