Home :: Blogs :: frank's blog

HOWTO: Install PECL APC Cache on CentOS (without XAMPP)

By frank - Posted on April 2nd, 2008
Tagged:  

As Irakli already discussed, the Alternative PHP Cache (APC) is an op-code pre-compiler and a cache system that can boost the performance of a PHP application up to 10 times. Op-code caches are very effective for a Drupal website, since Drupal deals with large number of source files and time spent in parsing them significantly affects performance.

However, if you don’t have XAMPP and need to install it on CentOS, you can follow this to get around some of the problems that happen with the default server settings.

Install Pre-reqs

Using yum install the required prerequisites.

sudo yum install php-devel php-pear httpd-devel


Install APC

Use the command

sudo pecl install apc

at this point you’ll likely see the error

Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 92160 bytes) in /usr/share/pear/PEAR/PackageFile/v2/Validator.php on line 1831

Apparantly, the PECL/PEAR scripts do not use the settings from /etc/php.ini so you need to update PEAR’s memory settings to give is some more breathing room. Edit the file /usr/share/pear/pearcmd.php and add the following at the beginning:

@ini_set('memory_limit', '16M');


Configure/Restart

Now configure PHP to use the new extension. Create the file /etc/php.d/apc.ini and in that file put:

extension=apc.so

Now restart apache

sudo /etc/init.d/httpd greaceful


Maintenance

In the future, if new versions of APC are released, you can easily upgrade them using

sudo pecl upgrade apc

I hope this helps!

frank

Frank is a founder of Phase2 and the Chief Technology Strategist. He is intensely focused on making all this cool tech do his bidding.


Bookmark/Search this post with:
Problem finding apxs
Submitted by frank on Wed, 09/24/2008 - 17:59.

If you run across the problem of

cannot open /httpd/build/config_vars.mk: No such file or directory at /usr/sbin/apxs line 201

The problem is likely that you do not have the x64 version of the apr-devel package installed. So you much first do:

yum install apr-devel.x86_64

Then you can proceed with the installation of APC. Hope this helps someone.

A simpler way of fixing the pecl memory problem
Submitted by Alain Williams (not verified) on Mon, 08/25/2008 - 18:12.

Rather than change /usr/share/pear/pearcmd.php (which is a large script that may be updated) change /usr/bin/pecl to include ‘’-d memory_limit=16M’‘. This is more likely to work well with system updates via yum — which may want to update pearcmd.php

I have suggested this fix to redhat — where I raised the bug

Nice!
Submitted by frank on Tue, 08/26/2008 - 11:25.

That is another good idea.

Recently, I have noticed since going to CentOS 5.2 that this problem no longer happens.