# test on DEBIAN 7 and php 5.4

Installing PHP-pear
 sudo apt-get install -y php-pear

then dependencies
 sudo apt-get install -y build-essential php5-dev

After I checkout latest version (Now It's 7.0.5) Installing the opcache.
 sudo pecl install zendopcache

Find extension directory
 sudo find / -name 'opcache.so'

Create config file for php
 nano /etc/php5/mods-available/opcache.ini'

Add these stuff in file (check path opcache.so):
 zend_extension=/usr/lib/php5/20100525...../opcache.so 
 opcache.memory_consumption=128
 opcache.interned_strings_buffer=8
 opcache.max_accelerated_files=4000
 opcache.revalidate_freq=60
 opcache.fast_shutdown=1
 opcache.enable_cli=1

Create a symlink for load this:
 sudo ln -s /etc/php5/mods-available/opcache.ini /etc/php5/conf.d/20-opcache.ini

The end restart the apache or there is any php-fpm you must restart this too

Then (optionally) finish by cleaning buil tools:
 sudo apt-get remove --purge build-essential php5-dev
 
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check:

php -v

It should give mention of
  Zend Engine v2.4.0, Copyright (c) 1998-2013 Zend Technologies
  with Zend OPcache v7.0.3, Copyright (c) 1999-2014, by Zend Technologies
  
or:
php -i | grep opcache
  
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