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I have a Rails application that I want to connect to a Redis data structure server. I'm wondering how I should proceed. I'm using a global variable $redis locate at config/initializers/redis.rb to make queries across the entire application.

I believe this approach it is not suitable for a application with 80+ simultaneous connections, because it uses one single global variable to handle the Redis connection.

What should I do to overcome this problem? am I missing something about Rails internals?

Tutorial I'm following http://jimneath.org/2011/03/24/using-redis-with-ruby-on-rails.html

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This depends on the application server you will use. If you're using Unicorn which is a popular choice you should be fine.

Unicorn forks it's workers and each one will establish it's own database connection. And since each worker can only handle one request at a time it will only need one connection at a time. Adding more connections won't increase performance, it just will open more (useless) connections.

ActiveRecord (which is the DB-part of Rails) or DataMapper support connection pooling which is a common solution to overcome the problem you've mentioned. Connection pooling however only make sense in a threaded environment.

On top of that Redis is mainly single threaded (search for "Single threaded nature of Redis") so there might be no advantages anyway. There was an request to add connection pooling but it got closed, you might get more information from there.

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Thank you, with your answer I was able to do some research and ended up using Unicorn. Although with Unicorn now I have memory issues, I learned that Ruby does not release the memory back to the Operative system, but instead reuses it, which is a big problem for me, because every fork Unicorn make, consumes as much memory as the Parent process. Last time I checked a single process of my application consumes +90mb, multiply that number by the number of process forked and becomes a considerable amount of memory, in the mean time, I'm doing GC.start after each fork.
@Kira Do you use Ruby 2? If not you should (see part about Copy-On-Write) and I think GC.start after forking isn't really useful, but Unicorn’s out-of-band GC might be.
Yes I'm using Ruby 2 for the same reasons you said; CoW. Although I was not aware of the "out of band GC" and that GC.start could be a bad idea; such a wonderful link the one you provided. Many thanks, 2called-chaos.

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