opcacheenablecli

opcache.enable_cli is a PHP INI directive that enables the Zend OPcache for the command-line interface (CLI) SAPI. It controls whether the opcode cache is used when PHP runs from the command line. When enabled, PHP CLI scripts can reuse cached opcodes across repeated executions within a single process, reducing compilation overhead for long-running CLI tasks or scripts that include many files. When disabled, CLI invocations bypass the opcode cache and each run compiles PHP files anew.

Configuration and usage: The directive is configured in the CLI's php.ini file, or via the PHP CLI command line using -d opcache.enable_cli=1. In most distributions, the default is off, so explicitly enabling it is required to see benefits. It interacts with other OPcache settings such as opcache.memory_consumption, opcache.max_accelerated_files, opcache.validate_timestamps, and opcache.revalidate_freq. If opcache.validate_timestamps is enabled, PHP will check script file timestamps to detect changes; in CLI environments this is commonly left enabled to ensure updated scripts are re-cached when needed, but for long-running CLI processes that should not be affected, it can be tuned with opcache.revalidate_freq.

Performance implications: Enabling opcache for CLI can improve performance for scripts that load many files or perform repetitive PHP execution in a single invocation. However, for short-lived CLI tasks that run once and exit, gains may be minimal.

Security and maintenance: Since the CLI environment often runs ad-hoc or cron-based tasks, operators should consider how recently scripts may be edited and the revalidation settings. Ensure the CLI PHP configuration matches the desired behavior across environments.