How can the performance impact of checking the timestamp on every script call be minimized in PHP?

Checking the timestamp on every script call can impact performance in PHP due to the overhead of file system operations. To minimize this impact, you can cache the timestamp value and only check the file modification time periodically or when necessary, rather than on every script call.

$cacheFile = 'cache.txt';
$cacheTime = file_exists($cacheFile) ? filemtime($cacheFile) : 0;
$currentTime = time();

if ($currentTime - $cacheTime > 60) { // Check timestamp every 60 seconds
    // Update cache file with current timestamp
    file_put_contents($cacheFile, $currentTime);
    
    // Perform necessary operations
    // ...
}