Rails action using an insane amount of MySQL/CPU

rubyonrails-talk
1

Danny,

1/ Try out the query analyzer plugin :    http://agilewebdevelopment.com/plugins/query_analyzer

In no time you'll know if your are missing some obvious indexes, the common cause for DB slowness.

.. and read this :     Indexing for DB performance     Buckblog: Indexing for DB performance

Alain Ravet

2

I would also recommend using the paginator gem instead of the built-in pagination of Rails. It is much more efficient. SInce I swapped them out, I've had no problems.

gem install paginator

documentation: http://paginator.rubyforge.org/

3

that would work, just be sure to update the links for next/prev with the new offset and limit

4

Also if you have all your images in the database, this could be the main cause for the slowness, send back so much data can take a while, even if the actual query is quick. I don't know it would be possible, but consider maybe using Amzon S3 service if your number of image will increase and the number of requests increase. Then just keep a reference of the names in database, this should inprove the effecientcy more.