Every event in a Laravel app, a page view, an API hit, a user action, typically writes to the database once, immediately. Under normal traffic that is fine. Under load it becomes a bottleneck: lock contention, slow response times, and a database that cannot keep up with a stream of individual inserts hitting it on every request.
The standard fix requires real infrastructure. Laravel queues, Redis, Horizon, Supervisor. On managed servers that is achievable but adds operational overhead. On shared hosting, those options are not available at all. Either way, you are adding significant complexity to solve what is fundamentally a write frequency problem.
Laravel Spool captures high-frequency writes to a fast local buffer first, then flushes them as a single batch on a schedule you control. One thousand individual inserts become one batch insert. The write cost moves off your HTTP response cycle entirely. The filesystem driver works anywhere PHP runs, with Redis Streams available as an optional upgrade when your infrastructure supports it.