#json performance

Scrutinize problem piece of code - 

Rather than using Ruby array manipulation functions on activerecord objects fetched, try to use the sql filter, order, group etc. via AREL

at = User.arel_table   

at1 = Object2.includes(:class3).where(at[:attribute1].lower.matches("%#{search_text.downcase}%"))

     2. While querying, include all the nested objects for eager loading.       Dramatic difference it makes - 

users = User.includes(:addresses => [{:countries => :city}, :designations]).where('id in (?) AND active = 1', user_ids)

    3. Now optimize the json encoding process - 

 Use Yajl library. Install like so

# Gemfile

gem 'yajl-ruby', :require => "yajl"

Use Yajl library

Ensure the engine used :

> MultiJson.engine

  Installation might give an error about Notifier, update your ruby gems - 

gem update --system

  4. Other JSON builders could also be chosen -

Representative

Tokamak

Builder

JSONify

Argonaut

JSON Builder

RABL

References:

https://groups.google.com/forum/?fromgroups=#!topic/rails-oceania/kGHfiHU3GG4

http://stackoverflow.com/questions/10451722/what-is-the-fastest-way-to-render-json-in-rails

Use Yajl library for JSON processing -

# Gemfile gem 'yajl-ruby', :require => "yajl"

Options

https://github.com/mdub/representative

https://github.com/inem/tequila https://github.com/abril/tokamak https://github.com/jbr/argonaut