php.ini tuning

gistfile1.md

ini files

• The CLI sapi is using a different ini file. Make sure you optimize both the web and CLI one.
• Scan your php.ini for best security practices with PHP iniscan tool.

memory

Save system resources by adjusting the memory_limit value. Don't know what an appropriate value would be? Ask yourself these questions:

• what is the total amount of memory that you can allocate for PHP?
  • 512mb should a reasonable amount for a 2gb machine)
• how much memory on average, is consumed by a single process?
  • check with memory_get_peak_usage(), this is often between 5-20mb
• how many PHP-processes can I afford?
  • if you have 512mb of memory allocated and each process takes 15mb, you can afford 34 processes

stress testing

Do you have enough system resources? (stress-test with Apache Bench or Siege before you go into production.

OPcache

Configure the Zend OPcache (php 5.5.0+)

• depending on application size, adjust opcache.memory_consumption: 16mb for small apps and 64 for large ones
• bump opcache.interned_strings_buffer (pointer buffer of identical strings) from 4mb to 16mb
• make sure that opcache.max_accelerated_files is larger than the number of files in your application
• disable opcache.validate_timestampts for production, but keep it enabled for development
• set opcache.revalidate_freq to 0, making sure that PHP checks compiled files for changes on every request during development
• turn on opcache.fast_shutdown by setting 1 which delegates object deconstruction

file uploads

Don't use file uploads? set file_uploads to 0 in order to improve security

You do?

• set a maximum upload filesize that your application accepts and maximum number of uploads that your application accepts at one time.
  • bump the upload_max_filesize setting to 10mb or higher according to the requirements
  • adjust the client_max_body_size in your nginx virtual host in addition to php.ini

max execution time

Set max_execution_time from 30 to 5.

sessions

Change the default session handler to a faster in-memory data store (like memcached or redis), eliminating unnecessary file I/O with a bonus of enabling future scalability. Be sure to change the session.save_handler.

output buffering

Change implicit_flush to false and make sure output_buffering is a multiple of 4 (32-bit system) or 8 (64-bit system).

realpath

Change the realpath_cache_size (cache of files so PHP does not have to search the include path) accordingly.

• check by bumping to 256k and then calling realpath_cache_size().