For performance improvements (and to remove the need for eager loading), the 
  ActsAsTaggableOn gem
  
    Show archive.org snapshot
  
 supports caching your tag lists directly in your model. To enable this, simply add a cached_tag_list column to your table.
Example:
class Company < ActiveRecord::Base
  acts_as_taggable_on :categories
end
The cache column has to be named cached_category_list.
Existing data
If you already have existing data, you have to save all records with tags once, after you've added the column, like this:
Company.all.each do |company|
  company.category_list # it seems you need to do this first to generate the list
  company.save!
end
Posted by Tobias Kraze to makandra dev (2011-11-25 09:29)