How to Install APC on CentOS 6 - Revision history

Docs admin at 19:20, 12 December 2012

2012-12-12T19:20:18Z

← Older revision		Revision as of 15:20, 12 December 2012
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	==Installing APC==		==Installing APC==

	Installation of ~~PHP~~ is straightforward on CentOS 6, there's a readily available RPM for PHP. You can easily install APC with yum:		Installation of APC is straightforward on CentOS 6, there's a readily available RPM for PHP. You can easily install APC with yum:

	<syntaxhighlight lang="bash">yum install php-pecl-apc</syntaxhighlight>		<syntaxhighlight lang="bash">yum install php-pecl-apc</syntaxhighlight>

Docs admin at 15:47, 5 December 2012

2012-12-05T15:47:52Z

← Older revision		Revision as of 11:47, 5 December 2012
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	Optionally, if you have GD installed, this script will display helpful graphs of your APC statistics. If you do not have GD installed, you can view the KB article on [[How to Install GD for PHP on CentOS 6]]		Optionally, if you have GD installed, this script will display helpful graphs of your APC statistics. If you do not have GD installed, you can view the KB article on [[How to Install GD for PHP on CentOS 6]]

	~~You can~~ copy this script to a web-accessible location ~~to view your APC's statistics~~. In our example, we'll copy it directly to our Apache's web root:		To use apc.php, simply copy this script to a web-accessible location. In our example, we'll copy it directly to our Apache server's web root:

	<syntaxhighlight lang="bash">mkdir /var/www/html/apc		<syntaxhighlight lang="bash">mkdir /var/www/html/apc
	cp /usr/share/doc/php-pecl-apc-*/apc.php /var/www/html/apc</syntaxhighlight>		cp /usr/share/doc/php-pecl-apc-*/apc.php /var/www/html/apc</syntaxhighlight>

	===apc.		===apc.conf.php===

			apc.php has an optional configuration file, apc.conf.php. The apc.php script gives you the ability to view user data or to clear your APC cache altogether. For this reason, we suggest setting an administrator username and password and this can be done using the apc.conf.php configuration file. Open this file in your favorite text editor, we'll use nano in our example:

			<syntaxhighlight lang="bash">nano /var/www/html/apc/apc.conf.php</syntaxhighlight>

			Add these lines to the file, replacing MYUSERNAME and MYPASSWORD with your desired username and password:

			<syntaxhighlight lang="bash">
			<?php
			defaults('ADMIN_USERNAME','MYUSERNAME');
			defaults('ADMIN_PASSWORD','MYPASSWORD');
			?>
			</syntaxhighlight>

			then save the file. This will password protect the sensitive areas of your apc.php script.

			===Example Output===

			If you visit apc.php in a browser, you should see output similar to the following image. Note that we have GD installed in this example so apc.php displays graphs of our cache performance.

			[[File:Apc php example output.png]]

	[[Category:APC]] [[Category:CentOS 6]]		[[Category:APC]] [[Category:CentOS 6]]

Docs admin at 15:35, 5 December 2012

2012-12-05T15:35:43Z

← Older revision		Revision as of 11:35, 5 December 2012
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	<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntaxhighlight>		<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntaxhighlight>

			==apc.php==

			Included with the APC RPM is the script apc.php. This script will break down your APC performance and give you statistics regarding cache usage and cache hits/misses. apc.php is located here:

			<syntaxhighlight lang="bash">/usr/share/doc/php-pecl-apc-*/apc.php</syntaxhighlight>

			Optionally, if you have GD installed, this script will display helpful graphs of your APC statistics. If you do not have GD installed, you can view the KB article on [[How to Install GD for PHP on CentOS 6]]

			You can copy this script to a web-accessible location to view your APC's statistics. In our example, we'll copy it directly to our Apache's web root:

			<syntaxhighlight lang="bash">mkdir /var/www/html/apc
			cp /usr/share/doc/php-pecl-apc-*/apc.php /var/www/html/apc</syntaxhighlight>

			===apc.

	[[Category:APC]] [[Category:CentOS 6]]		[[Category:APC]] [[Category:CentOS 6]]

Docs admin at 17:41, 4 December 2012

2012-12-04T17:41:02Z

← Older revision		Revision as of 13:41, 4 December 2012
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	APC (Alternative PHP Cache) is an opcode cache for PHP. APC provides a caching system for intermediate PHP code and ~~gain~~ greatly increase PHP performance. PHP is an interpreted language, meaning, the code is interpreted on each request for a file. When a visitor requests a PHP script, the PHP code is read, interpreted into bytecode and then executed. PHP's Zend Engine does the interpreting very quickly, but when you are serving hundreds or thousands of requests per seconds, every CPU cycle counts.		APC (Alternative PHP Cache) is an opcode cache for PHP. APC provides a caching system for intermediate PHP code and can greatly increase PHP performance. PHP is an interpreted language, meaning, the code is interpreted on each request for a file. When a visitor requests a PHP script, the PHP code is read, interpreted into bytecode and then executed. PHP's Zend Engine does the interpreting very quickly, but when you are serving hundreds or thousands of requests per seconds, every CPU cycle counts.

	This is where APC comes in. APC allows your webserver to cache the interpreted bytecode directly, there's no need to re-read the PHP script and re-interpret it. Knowing that the PHP source code of your website rarely changes, this can greatly speed up your web applications.		This is where APC comes in. APC allows your webserver to cache the interpreted bytecode directly, there's no need to re-read the PHP script and re-interpret it. Knowing that the PHP source code of your website rarely changes, this can greatly speed up your web applications.

Docs admin at 23:28, 30 November 2012

2012-11-30T23:28:02Z

← Older revision		Revision as of 19:28, 30 November 2012
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	[Category:APC] [Category:CentOS 6]		[[Category:APC]] [[Category:CentOS 6]]

Docs admin at 23:27, 30 November 2012

2012-11-30T23:27:51Z

← Older revision		Revision as of 19:27, 30 November 2012
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	<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntaxhighlight>		<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntaxhighlight>


			[Category:APC] [Category:CentOS 6]

Docs admin at 23:25, 30 November 2012

2012-11-30T23:25:34Z

← Older revision		Revision as of 19:25, 30 November 2012
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	Installation of PHP is straightforward on CentOS 6, there's a readily available RPM for PHP. You can easily install APC with yum:		Installation of PHP is straightforward on CentOS 6, there's a readily available RPM for PHP. You can easily install APC with yum:

	<syntaxhighlight lang="bash">php-pecl-apc</syntaxhighlight>		<syntaxhighlight lang="bash">yum install php-pecl-apc</syntaxhighlight>

	As always, be sure to restart your web server after installation for the new module to take effect. If you're using Apache, you can run:		As always, be sure to restart your web server after installation for the new module to take effect. If you're using Apache, you can run:

Docs admin at 23:16, 30 November 2012

2012-11-30T23:16:41Z

← Older revision		Revision as of 19:16, 30 November 2012
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	Installation of PHP is straightforward on CentOS 6, there's a readily available RPM for PHP. You can easily install APC with yum:		Installation of PHP is straightforward on CentOS 6, there's a readily available RPM for PHP. You can easily install APC with yum:

	<syntaxhighlight lang="bash">php-pecl-apc</~~syntax~~>		<syntaxhighlight lang="bash">php-pecl-apc</syntaxhighlight>

	As always, be sure to restart your web server after installation for the new module to take effect. If you're using Apache, you can run:		As always, be sure to restart your web server after installation for the new module to take effect. If you're using Apache, you can run:

	<syntaxhighlight lang="bash">/etc/init.d/httpd restart</~~syntax~~>		<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntaxhighlight>

	==Configuring APC==		==Configuring APC==
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	Installing APC via yum will generate an apc.ini file which can be modified to tweak your APC installation. The apc.ini file is located here:		Installing APC via yum will generate an apc.ini file which can be modified to tweak your APC installation. The apc.ini file is located here:

	<syntaxhighlight lang="bash">/etc/php.d/apc.ini</~~syntax~~>		<syntaxhighlight lang="bash">/etc/php.d/apc.ini</syntaxhighlight>

	The popular eCommerce software Magento specifically suggests using APC to speed up performance. We're going to provide our recommended APC settings for use with Magento. You may find that other settings provide better performance for other applications, but these recommendations should give you a good starting point.		The popular eCommerce software Magento specifically suggests using APC to speed up performance. We're going to provide our recommended APC settings for use with Magento. You may find that other settings provide better performance for other applications, but these recommendations should give you a good starting point.
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	This ini directive is one of the most important ones. This controls how much memory APC will use to cache PHP opcode. By default, the value is set at 64M. While this may work for smaller sites, we generally recommend increasing this to get the best performance from APC. We suggest setting it to 128M, but if you have more free RAM available, you may find increasing it beyond this will further speed up your site:		This ini directive is one of the most important ones. This controls how much memory APC will use to cache PHP opcode. By default, the value is set at 64M. While this may work for smaller sites, we generally recommend increasing this to get the best performance from APC. We suggest setting it to 128M, but if you have more free RAM available, you may find increasing it beyond this will further speed up your site:

	<syntaxhighlight lang="bash">apc.shm_size=128M</~~syntax~~>		<syntaxhighlight lang="bash">apc.shm_size=128M</syntaxhighlight>

	Take note that the value must be followed by an M or G to denote megabytes or gigabytes.		Take note that the value must be followed by an M or G to denote megabytes or gigabytes.
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	This directive defines whether APC will check a requested PHP file for modifications since the last time it was cached. Leaving this variable set to 1 is often useful in a development environment where you may be frequently modifying code. If you're using APC in a production environment, you can gain additional performance by setting this to 0. When upgrades are necessary, you can update your code and restart your webserver to clear the APC cache.		This directive defines whether APC will check a requested PHP file for modifications since the last time it was cached. Leaving this variable set to 1 is often useful in a development environment where you may be frequently modifying code. If you're using APC in a production environment, you can gain additional performance by setting this to 0. When upgrades are necessary, you can update your code and restart your webserver to clear the APC cache.

	<syntaxhighlight lang="bash">apc.stat=0</~~syntax~~>		<syntaxhighlight lang="bash">apc.stat=0</syntaxhighlight>

	===apc.num_files_hint===		===apc.num_files_hint===
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	The apc.num_files_hint directive helps APC know how many unique files you plan to cache and can help APC better manage the memory cache. We suggest setting this value to 10000.		The apc.num_files_hint directive helps APC know how many unique files you plan to cache and can help APC better manage the memory cache. We suggest setting this value to 10000.

	<syntaxhighlight lang="bash">apc.num_files_hint=10000</~~syntax~~>		<syntaxhighlight lang="bash">apc.num_files_hint=10000</syntaxhighlight>

	===apc.user_entries_hint===		===apc.user_entries_hint===
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	apc.user_entries_hint gives APC a hint about how many distinct user cache variables you plan to store. We recommend a setting of 10000 for this directive as well.		apc.user_entries_hint gives APC a hint about how many distinct user cache variables you plan to store. We recommend a setting of 10000 for this directive as well.

	<syntaxhighlight lang="bash">apc.user_entries_hint=10000</~~syntax~~>		<syntaxhighlight lang="bash">apc.user_entries_hint=10000</syntaxhighlight>

	===apc.max_file_size===		===apc.max_file_size===
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	This directive defines the largest single file you want to cache. Files larger than this size will not be cached by APC. We suggest a value of 5M.		This directive defines the largest single file you want to cache. Files larger than this size will not be cached by APC. We suggest a value of 5M.

	<syntaxhighlight lang="bash">apc.max_file_size=5M</~~syntax~~>		<syntaxhighlight lang="bash">apc.max_file_size=5M</syntaxhighlight>

	===Restart httpd===		===Restart httpd===
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	Once again, restart httpd for the settings to take effect.		Once again, restart httpd for the settings to take effect.

	<syntaxhighlight lang="bash">/etc/init.d/httpd restart</~~syntax~~>		<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntaxhighlight>

Docs admin: Created page with "APC (Alternative PHP Cache) is an opcode cache for PHP. APC provides a caching system for intermediate PHP code and gain greatly increase PHP performance. PHP is an interpre..."

2012-11-30T23:16:12Z

Created page with "APC (Alternative PHP Cache) is an opcode cache for PHP. APC provides a caching system for intermediate PHP code and gain greatly increase PHP performance. PHP is an interpre..."

New page

APC (Alternative PHP Cache) is an opcode cache for PHP. APC provides a caching system for intermediate PHP code and gain greatly increase PHP performance. PHP is an interpreted language, meaning, the code is interpreted on each request for a file. When a visitor requests a PHP script, the PHP code is read, interpreted into bytecode and then executed. PHP's Zend Engine does the interpreting very quickly, but when you are serving hundreds or thousands of requests per seconds, every CPU cycle counts.

This is where APC comes in. APC allows your webserver to cache the interpreted bytecode directly, there's no need to re-read the PHP script and re-interpret it. Knowing that the PHP source code of your website rarely changes, this can greatly speed up your web applications.

==Installing APC==

Installation of PHP is straightforward on CentOS 6, there's a readily available RPM for PHP. You can easily install APC with yum:

<syntaxhighlight lang="bash">php-pecl-apc</syntax>

As always, be sure to restart your web server after installation for the new module to take effect. If you're using Apache, you can run:

<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntax>

==Configuring APC==

Installing APC via yum will generate an apc.ini file which can be modified to tweak your APC installation. The apc.ini file is located here:

<syntaxhighlight lang="bash">/etc/php.d/apc.ini</syntax>

The popular eCommerce software Magento specifically suggests using APC to speed up performance. We're going to provide our recommended APC settings for use with Magento. You may find that other settings provide better performance for other applications, but these recommendations should give you a good starting point.

===apc.shm_size===

This ini directive is one of the most important ones. This controls how much memory APC will use to cache PHP opcode. By default, the value is set at 64M. While this may work for smaller sites, we generally recommend increasing this to get the best performance from APC. We suggest setting it to 128M, but if you have more free RAM available, you may find increasing it beyond this will further speed up your site:

<syntaxhighlight lang="bash">apc.shm_size=128M</syntax>

Take note that the value must be followed by an M or G to denote megabytes or gigabytes.

===apc.stat===

This directive defines whether APC will check a requested PHP file for modifications since the last time it was cached. Leaving this variable set to 1 is often useful in a development environment where you may be frequently modifying code. If you're using APC in a production environment, you can gain additional performance by setting this to 0. When upgrades are necessary, you can update your code and restart your webserver to clear the APC cache.

<syntaxhighlight lang="bash">apc.stat=0</syntax>

===apc.num_files_hint===

The apc.num_files_hint directive helps APC know how many unique files you plan to cache and can help APC better manage the memory cache. We suggest setting this value to 10000.

<syntaxhighlight lang="bash">apc.num_files_hint=10000</syntax>

===apc.user_entries_hint===

apc.user_entries_hint gives APC a hint about how many distinct user cache variables you plan to store. We recommend a setting of 10000 for this directive as well.

<syntaxhighlight lang="bash">apc.user_entries_hint=10000</syntax>

===apc.max_file_size===

This directive defines the largest single file you want to cache. Files larger than this size will not be cached by APC. We suggest a value of 5M.

<syntaxhighlight lang="bash">apc.max_file_size=5M</syntax>

===Restart httpd===

Once again, restart httpd for the settings to take effect.

<syntaxhighlight lang="bash">/etc/init.d/httpd restart</syntax>