Certainly! Here are steps to optimize PHP-FPM to handle sudden spikes in traffic:

1. **Adjust PHP-FPM Configuration Parameters:**

   Edit the PHP-FPM configuration file `/etc/php/7.4/fpm/pool.d/www.conf`:

   ```bash
   sudo nano /etc/php/7.4/fpm/pool.d/www.conf
   ```

   Adjust the following parameters based on your server resources and expected traffic spikes:

   - `pm.max_children`: Increase the maximum number of child processes PHP-FPM can spawn. This allows PHP-FPM to handle more concurrent connections.
   
   - `pm.start_servers`: Increase the number of child processes PHP-FPM starts when it's initially started or restarted. This ensures there are enough processes available to handle incoming requests immediately.
   
   - `pm.min_spare_servers`: Increase the minimum number of spare processes PHP-FPM keeps alive to handle incoming requests during normal operation.
   
   - `pm.max_spare_servers`: Increase the maximum number of spare processes PHP-FPM keeps alive to handle incoming requests during peak traffic.
   
   - `pm.max_requests`: Increase the number of requests a child process can handle before it's terminated and replaced with a new one. This helps prevent memory leaks and ensures processes are periodically refreshed.

   Save the file and restart PHP-FPM:

   ```bash
   sudo systemctl restart php7.4-fpm
   ```

2. **Implement Process Management:**

   Use process management tools to monitor and manage PHP-FPM processes. Tools like Monit or Supervisor can automatically restart PHP-FPM processes if they consume too much memory or fail to respond.

3. **Enable PHP Opcode Cache:**

   As mentioned earlier, enabling an opcode cache like OPcache helps reduce the overhead of parsing and compiling PHP scripts on each request, leading to improved performance during traffic spikes.

4. **Optimize PHP Code:**

   Continuously optimize your PHP code for performance. This includes minimizing database queries, reducing file I/O operations, and optimizing algorithms. Efficient code ensures PHP-FPM processes can handle more requests with the available resources.

5. **Monitor and Scale Resources:**

   Continuously monitor server resources like CPU usage, memory usage, and disk I/O during traffic spikes. Use monitoring tools like Prometheus, Grafana, or New Relic to identify bottlenecks and scale resources as needed. Consider scaling vertically (upgrading server resources) or horizontally (adding more servers) to handle increased traffic.

Implementing these optimizations should help PHP-FPM handle sudden spikes in traffic more effectively, ensuring your server remains responsive and available during peak loads. Adjust configurations based on your specific requirements and traffic patterns.