Timeout error

Hi,

Could anyone help with an error I'm getting when running the following
code, it works on smaller sites but when I run it on a larger site it
times out...

doc = open("http://"+@theurl) { |f| Hpricot(f) }

I've found a few resources which mention how to increase the timeout
limit in Ruby on Rails but nothing which has worked, or I understand!

The error is ...

Timeout::Error in PostsController#index

execution expired

RAILS_ROOT: /Users/richardsmith/Documents/Creative Technologist/
SitemapCreator/Tester
Application Trace | Framework Trace | Full Trace

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/timeout.rb:60:in `rbuf_fill'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/net/protocol.rb:132:in `rbuf_fill'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/net/protocol.rb:116:in `readuntil'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/net/protocol.rb:126:in `readline'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/net/http.rb:2020:in `read_status_line'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/net/http.rb:2009:in `read_new'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/net/http.rb:1050:in `request'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:248:in `open_http'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/net/http.rb:543:in `start'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:242:in `open_http'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:616:in `buffer_open'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:164:in `open_loop'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:162:in `catch'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:162:in `open_loop'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:132:in `open_uri'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:518:in `open'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/
1.8/open-uri.rb:30:in `open'
/Users/richardsmith/Documents/Creative Technologist/SitemapCreator/
Tester/app/controllers/posts_controller.rb:42:in `processsitemap'