Caching on ruby on rails

Caching with Ruby on Rails
Scaling Rails - 第五章 Advanced Page Caching
Scaling Rails - 第六章 Action Caching
Scaling Rails - 第七章 Fragment Caching
Scaling Rails - 第八章 Memcached
Ruby on Rails Caching Tutorial
Sql cache
Query caches are created at the start of an action and destroyed at the end of that action and thus persist only for the duration of the action.

Rails 2.2.2 經測試, 在action, view, helper 裡default 都已有query cache, 只有在model 沒有, 還是必須使用
query cache
<br /> def self.query_cache <br /> User.cache do <br /> User.all <br /> User.all <br /> User.all <br /> end <br /> end <br />

adv cache,memcahe

http://nubyonrails.com/articles/about-this-blog-memcached
http://blog.leetsoft.com/2007/5/22/the-secret-to-memcached
http://blog.craigambrose.com/past/2007/11/13/caching_makes_your_brain_explode/
http://ryandaigle.com/articles/2007/12/19/what-s-new-in-edge-rails-pluggable-controller-caching
http://wiki.rubyonrails.org/rails/pages/MemCached
http://ihower.idv.tw/blog/archives/1768
http://www.ibm.com/developerworks/cn/web/wa-rails1/

Don’t Expire, Just Render it Obsolete

So, here’s my first bit of advice. If you’re building a real site, go straight to memcache. If you’re not building a site for big traffic, don’t cache, just optimise any really stupid queries that are giving you trouble. If you’re using memcache, be sure to run monit too.

memcached,cache

http://bbs.railschina.com/viewthread.php?tid=535
http://totou-phpmysql.blogspot.com/2008/07/memcached.html
http://www.danga.com/memcached/
http://nubyonrails.com/articles/memcached-basics-for-rails
http://www.gisblogs.net/post/183.html

cache in rails 2.1

http://railscasts.com/episodes/115-caching-in-rails-2-1
http://thewebfellas.com/blog/2008/6/9/rails-2-1-now-with-better-integrated-caching

cache的用法
<br /><br /># Write a string to the cache<br />Rails.cache.write('test_key', 'test_value')<br />=> true<br /><br /># Read it back in<br />Rails.cache.read('test_key')<br />=> 'test_value'<br /><br /># Delete the item<br />Rails.cache.delete('test_key')<br />=> true<br /><br />#find, if does not exist create<br />Rails.cache.fetch('now') { Time.now}<br /><br /><br />

有幾種cache 機制
<br /><br /># Use the memory store - this store has no options<br />config.cache_store = :memory_store<br /><br /># Use the file store with a custom storage path (if the directory doesn’t already exist it will be created)<br />config.cache_store = :file_store, '/my_cache_path'<br /><br /># Use the memcached store with default options (localhost, TCP port 11211)<br />config.cache_store = :mem_cache_store<br /><br /># Use the memcached store with an options hash<br />config.cache_store = :mem_cache_store, 'localhost', '192.168.1.1:1001', :namespace => 'test'<br /><br />

自己生個cache object
<br /><br /># Create a separate memory cache in addition to the global Rails cache<br />my_cache = ActiveSupport::Cache.lookup_store(:memory_cache)<br /><br />

幫助你生cache_key
<br /><br />>> u = User.first<br />=> #<user><br />>> u.cache_key<br />=> "users/1-20081114035214"<br />

memcachestore 是production 常選用的方式, default 存入是存成marshal
<br /># Write a raw value to the cache<br />Rails.cache.write('test_key', 1, :raw => true)<br /><br /># Read a raw value from the cache<br />Rails.cache.read('test_key', :raw => true)<br /><br /># Write a value using the add method and setting expiry to 15 minutes<br />Rails.cache.write('test_key', 'test_value', :unless_exist => true, :expires_in => 15.minutes)<br /><br />

cache,page

http://www.javaworld.com.tw/jute/post/view?bid=59&id=191117&sty=3&age=0&tpg=1&ppg=1
http://api.rubyonrails.org/classes/ActionController/Caching/Pages.html#M000282

# In Rails 2.1 you can use :if option
caches_page :index, :if => Proc.new { |c| !c.request.format.json? } <=不是json才會cache