Difference between revisions of "Install Redis Full Page Caching for Magento Enterprise"

Revision as of 16:42, 24 December 2013

Install Redis Full Page Caching for Magento Enterprise

How to install redis for full page caching? You see alot of talk about using apc for Magento caching, but if you are looking for a stable caching, then redis is for you.

1) Install Redis and phpRedis

This can be done using yum, which makes this step pretty easy.

yum install redis php-pecl-redis

service redis start

chkconfig redis on

Now to verify that redis is chkconfig on

chkconfig --list redis

2) Install Cm_Cache_Backend_Redis Magento Extension

This is the extension that is required on versions of CE 1.7.0.2 and older, as Magento 1.8.0.0 it comes pre installed.

wget -O Cm_Cache_Backend_Redis.tar.gz https://github.com/colinmollenhour/Cm_Cache_Backend_Redis/tarball/master

tar xzf Cm_Cache_Backend_Redis.tar.gz 

cd colinmollenhour-Cm_Cache_Backend_Redis-9bd58d2/

cp Cm_Cache_Backend_Redis/Cm /path/to/magento/app/code/local/

cp Cm_Cache_Backend_Redis/lib/Credis /path/to/magento/lib/

cat > /path/to/magento/app/etc/modules/Cm_Cache.xml <<eof
<?xml version="1.0" encoding="UTF-8"?>
<config>
   <modules>
       <Cm_Cache>
           <active>true</active>
           <codePool>local</codePool>
       </Cm_Cache>
   </modules>
</config>
eof

3) Install Credis Library

Again not needed if you are using Magento 1.8.0.0 or higher, as its already included in the base install

wget -O credis.tar.gz https://github.com/colinmollenhour/credis/tarball/master

tar xzf credis.tar.gz

cd colinmollenhour-credis-5a48ac8/

cp ./* /path/to/magento/lib/Credis/

cd /path/to/magento/

chown -R username. lib/Credis/

chown -R username. app/code/local/Cm/

chown -R username. app/etc/modules/Cm_Cache.

4) Configure Magento to use Redis for Full Page Caching

I recommend always making a backup copy of your local.xml file before making any changes to it

cp app/etc/local.xml app/etc/local.xml-bk-date

Now lets install redis as a backend cache

vim app/etc/local.xml

Now add the following to your configuration

<full_page_cache>
  <backend>Cm_Cache_Backend_Redis</backend>
  <backend_options>
    <server>127.0.0.1</server> 
    <port>6379</port>
    <persistent></persistent> 
    <password></password> 
    <force_standalone>0</force_standalone>  
    <connect_retries>1</connect_retries>    
    <lifetimelimit>57600</lifetimelimit>    
    <compress_data>0</compress_data>        
  </backend_options>
</full_page_cache>

Clearning your Magento Cache

Now the last step is a giving, any time you make any changes to your Magento configuration/template is to clear your sessions and cache. You do NOT want problems later, because you forgot to clear them and you now find a problem. Sometimes problems show their heads up to a week or so, so clear cache/session and see if you have any problems/issues.

If you were using files prior to the change

rm -r /path/magento/var/session/* /path/magento/var/cache/*

If you were using memcache prior to change

echo "flush_all" | nc 127.0.0.1 11211

or if using a sock

echo "flush_all" | nc -U /path/to/socket

How to flush your Redis Cache

Now you will want to flush your redis cache anytime you make a change to your site. The fastest way to do this is to run the following command via the command line.

echo 'flushall' | redis-cli -h 127.0.0.1 -p 6379

Add a second instance of Redis

Redis is single-threaded so it’s performance peaks when it uses one full CPU core. On a multi-core machine (every machine these days) your peak performance with Redis will be higher if you can use multiple cores. Also, there will be no waiting between different processes. E.g. while one process may be fetching the config, another would be waiting to load a session and another would be waiting to load a FPC record. By having each on a separate core you have much higher peak performance and less contention.

cp /etc/redis.conf /etc/redis2.conf && cp /etc/init.d/redis /etc/init.d/redis2

Change

vim /etc/init.d/redis2
pidfile="/var/run/redis/redis.pid" to pidfile="/var/run/redis/redis2.pid"
REDIS_CONFIG="/etc/redis.conf" to REDIS_CONFIG="/etc/redis2.conf"

Change

vim /etc/redis2.conf
port 6379 to port 6380
unixsocket /tmp/redis.sock to unixsocket /tmp/redis2.sock

service redis2 start

Let also make this instance start up on boot

chkconfig redis2 on

Now verify its set to start at boot

chkconfig --list redis2

redis2          0:off   1:off   2:on    3:on    4:on    5:on    6:off