Configuring Your php.ini File
Why Change Your php.ini file?
Both PHP for Windows and Linux ship with pre-configured .ini files with settings common to most PHP setups. The Windows installer (which I recommend if you’re using Windows for a development machine, or even have your live site on Windows) goes a step further and also will add lines to your php.ini file through a simple GUI that enable both your web server and desired PHP extensions.
Most people will leave these the rest of the .ini file unchanged, but there are some changes that can make life much easier. Below are my recommendations for changes to the default php.ini file. The line number is next to each changed line, and is accurate for Windows PHP 5.25 distributions.
Short Tags
Short tags are PHP tags like this <? ?> and were very common a few years ago and taught to me in my Web Technologies class at NYU. You should generally allow these, especially if you are working with inherited code. This setting was the cause of over an hour of frustration when I moved an application to a new server and it suddenly wouldn’t load.
Orig: short_open_tag = Off Mine: short_open_tag = On
Maximum Execution Time
For some reason this is only set to 30 seconds by default. Some heavy hitting scripts that write to disk, retrieve information from the web, or other things where waiting is involved, can run longer than 30 seconds. The cron.php script for a Drupal site that I work on customarily runs for over a minute.
Orig: max_execution_time = 30 Mine: max_execution_time = 240
Memory Limit
I’ve found that many high traffic sites will run out of memory when this is set to 128m. This setting is per script, so if 10 scripts are executing at once, you can easily max out your memory. If you’re using more than 64m for a certain script, you need to optimize your code, or split up functionality into more than one script.
Orig: memory_limit = 128M Mine: memory_limit = 64M
Display Errors
I would recommend the following change only for development machines, not live severs. When set to “On”, PHP will output the error directly to
Orig: display_errors = Off Mine: display_errors = On
Error Log
This is another setting I would only recommend doing on a development machine, not a live server. When uncommented and supplied with a valid filename, this will output all errors and warnings to an error log file in the base directory of your server root. Again, very helpful for debugging and development.
Orig: ;error_log = filename Mine: error_log = errors.txt
Upload Filesize
On the chance that you are uploading files in your scripts, this is a handy change to make. I’ve found that 4M is a much friendlier setting, especially with digital picture uploads, which are regularly more than 2M.
Orig: upload_max_filesize = 2M Mine: upload_max_filesize = 4M
Session Name
When using sessions, PHP will create cookies to store information and the below setting will be the name of the cookie. When in doubt, give a malicious user as little information as possible, and this setting exposes the fact that you are using PHP sessions. Pick a more general name.
Orig: session.name = PHPSESSID Mine: session.name = XYZ
Don’t forget to restart your web server after making any of the above changes.
About
Elliott Brueggeman is a Seattle based Software Developer with interests in PHP, MYSQL, and the development of high traffic web sites. Follow me on Twitter at http://twitter.com/ebrueg.