Are there any potential pitfalls or drawbacks when using the parallel extension in PHP?

One potential pitfall when using the parallel extension in PHP is the risk of race conditions, where multiple threads access and modify shared data simultaneously, leading to unpredictable behavior. To avoid this issue, it is important to properly synchronize access to shared resources using locks or other synchronization mechanisms.

$lock = new \parallel\Sync\Lock();

\parallel\run(function() use ($lock) {
    $lock->acquire();
    // Critical section
    $lock->release();
});

\parallel\run(function() use ($lock) {
    $lock->acquire();
    // Critical section
    $lock->release();
});