Boost PHP7 Performance: 5 Essential Tweaks You Must Enable

PHP 7 has been released as the biggest version upgrade in a decade, delivering noticeable performance gains, but to fully exploit its speed you should apply several optimizations.

1. Enable Zend Opcache

Even without Opcache, PHP 7 outperforms PHP 5.6 with Opcache, so be sure to enable it by adding the following lines to php.ini:

zend_extension=opcache.so opcache.enable=1 opcache.enable_cli=1

2. Use a Newer Compiler

Compile PHP with GCC 4.8 or newer. Versions 4.8+ activate the Global Register for opline and execute_data, yielding roughly a 5% performance boost in WordPress‑style workloads. Older GCC versions may support the feature but contain bugs, so stick to 4.8 or later.

3. Enable HugePages

Activate HugePages at the OS level and then enable opcache.huge_code_pages in php.ini to let PHP store its text segment and memory allocations on large pages, reducing TLB misses.

On CentOS 6.5 you can reserve 512 huge pages with:

sudo sysctl vm.nr_hugepages=512

Verify the allocation:

cat /proc/meminfo | grep Huge

Then add the following to php.ini:

opcache.huge_code_pages=1

4. Enable Opcache File Cache (Experimental)

Store compiled opcodes in external files to improve script performance by adding:

opcache.file_cache=/tmp

This creates binary opcode cache files under /tmp that persist across PHP processes.

5. Apply Profile‑Guided Optimization (PGO)

If PHP is dedicated to a single project (e.g., a specific WordPress site), you can build a PGO‑optimized binary:

Generate profiling instrumentation: make prof-gen Run the target workload to collect profiles, for example:

sapi/cgi/php-cgi -T 100 /home/huixinchen/local/www/htdocs/wordpress/index.php >/dev/null

Finalize the optimized build:

make prof-clean

make prof-use

The resulting PHP 7 binary is tuned for maximum performance on your specific application.

These five steps provide a solid foundation for squeezing the best speed out of PHP 7.