PHP opcache_is_script_cached() Function: Usage and Examples

Checks whether a script path is currently present in the OPcache of the active SAPI.

What It Does and When to Use It

Ask whether a specific resolved path is cached in the active SAPI. OPcache caches compiled opcodes, JIT may optimize CPU-intensive PHP, while APCu caches application-owned values.

Requirements, Inputs and Expected Behavior

Confirm the runtime, extension, environment variables, and permissions before running the examples in production. CLI and FPM caches are separate; path and cache-warming timing affect results.

Example 1: Basic Operation

Ask whether a specific resolved path is cached in the active SAPI.

<?php
$file = realpath(__FILE__);
 if ($file !== false) var_dump(opcache_is_script_cached($file));

Example 2: Behavior and Validation

Check the effective configuration when a file is not cached.

<?php
$settings = opcache_get_configuration()['directives'] ?? [];
 echo 'OPcache: ', (int)($settings['opcache.enable'] ?? 0);

Practical Example: Application Use

Compare cached status for the current file and another application script.

<?php
foreach ([__FILE__, __DIR__ . '/bootstrap.php'] as $candidate) {
     $resolved = realpath($candidate);
     echo basename($candidate), ': ', ($resolved && opcache_is_script_cached($resolved) ? 'cached' : 'not cached'), "
";
 }

Important Behavior and Edge Cases

The second example highlights: Check the effective configuration when a file is not cached. The practical example adds: Compare cached status for the current file and another application script.

Comparison with Related Approaches

Common Beginner Mistakes

Key Takeaways

• Checks whether a script path is currently present in the OPcache of the active SAPI.
• Compare cached status for the current file and another application script.
• Profile application response times and memory under representative traffic before tuning.