PHP Environment Variables

LSAPI Environment Variables

These environment variables control how lsphp worker processes behave. Set them in the extprocessor configuration in httpd_config.conf:

extprocessor lsphp {
  type                    lsapi
  ...
  env                     PHP_LSAPI_CHILDREN=10
  env                     LSAPI_MAX_REQS=5000
  env                     PHP_LSAPI_MAX_IDLE=300
  env                     LSAPI_AVOID_FORK=0
  env                     LSAPI_ACCEPT_NOTIFY=1
}

Variable Reference

Variable	Default	Description
`PHP_LSAPI_CHILDREN`	10	Number of PHP worker processes. Each handles one request at a time.
`LSAPI_MAX_REQS`	10000	Requests a worker serves before exiting and being replaced. Lower values help prevent memory leaks.
`PHP_LSAPI_MAX_IDLE`	300	Seconds a worker can sit idle before being terminated.
`LSAPI_AVOID_FORK`	0	Set to `1` to use `exec()` instead of `fork()` for new workers. Useful on systems with overcommit disabled.
`LSAPI_ACCEPT_NOTIFY`	1	Notify parent process when a child accepts a connection. Enables better load balancing.
`LSAPI_PGRP_MAX_IDLE`	300	Seconds the entire process group can be idle before all workers exit.
`LSAPI_MAX_IDLE_CHILDREN`	PHP_LSAPI_CHILDREN / 3	Maximum number of idle children to keep alive.
`LSAPI_MAX_PROCESS_TIME`	300	Maximum seconds a single request can take before the worker is killed.

Sizing PHP_LSAPI_CHILDREN

The number of children directly impacts concurrency and memory usage.

Formula:

PHP_LSAPI_CHILDREN = Available_Memory_MB / Per_Worker_MB

Typical per-worker memory usage:

Application	Per-worker memory
Static PHP (phpinfo)	20-30 MB
WordPress	40-60 MB
Laravel	50-80 MB
Magento	80-120 MB

Example: A server with 4 GB available for PHP running WordPress:

4096 MB / 60 MB = ~68 workers (conservative: 50)

Set maxConns in the extprocessor to match PHP_LSAPI_CHILDREN.

php.ini Location

Each lsphp version has its own php.ini:

/usr/local/lsws/lsphp84/etc/php/8.4/litespeed/php.ini

If this file does not exist, lsphp falls back to:

/usr/local/lsws/lsphp84/etc/php.ini

To find the active configuration:

/usr/local/lsws/lsphp84/bin/lsphp -i | grep "Loaded Configuration File"

Common php.ini Tuning

Memory and Upload Limits

memory_limit = 256M
upload_max_filesize = 64M
post_max_size = 64M
max_execution_time = 300
max_input_time = 300
max_input_vars = 5000

OPcache Settings

OPcache is critical for PHP performance. Enable and tune it:

opcache.enable = 1
opcache.memory_consumption = 256
opcache.interned_strings_buffer = 16
opcache.max_accelerated_files = 10000
opcache.revalidate_freq = 60
opcache.validate_timestamps = 1
opcache.save_comments = 1
opcache.fast_shutdown = 1

For production servers where code does not change frequently:

opcache.validate_timestamps = 0

This disables file modification checks. You must restart lsphp after deploying new code.

Session Configuration

session.save_handler = files
session.save_path = /tmp
session.gc_maxlifetime = 1440

For multi-server setups, use Redis or Memcached:

session.save_handler = redis
session.save_path = "tcp://127.0.0.1:6379"

Error Logging

display_errors = Off
log_errors = On
error_log = /var/log/php/error.log
error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT

Per-Directory PHP Settings with LiteHTTPD

When the LiteHTTPD module is installed, you can override php.ini values per directory using .htaccess:

php_value memory_limit 512M
php_value upload_max_filesize 128M
php_value post_max_size 128M
php_flag display_errors Off

Applying Changes

After modifying environment variables in httpd_config.conf:

systemctl restart lsws

After modifying php.ini:

# Full restart
systemctl restart lsws

# Or gracefully restart just lsphp
killall -USR1 lsphp

Monitoring PHP Workers

Check the current number of lsphp processes:

ps aux | grep lsphp | grep -v grep | wc -l

Monitor memory usage per worker:

ps -C lsphp -o pid,rss,vsz,pcpu,args --sort=-rss

Next Steps

PHP LSAPI — detailed LSAPI architecture
Install PHP — install additional PHP versions