ScyllaDB's I/O Scheduler plays a crucial role in managing workloads and ensuring efficient operations by prioritizing requests to modern SSDs, optimizing latency, and maintaining throughput. The scheduler identifies the maximum useful disk concurrency to prevent latency spikes caused by queuing excess requests at the disk level, instead managing them within the database. Recent improvements address issues such as the differentiation between read and write speeds, request size considerations, and better user understanding of throughput. By applying Little’s Law, ScyllaDB can dynamically adjust concurrency to maintain optimal performance, reducing latency significantly in various scenarios. These enhancements are set to be included in ScyllaDB 2.3, promising even better performance for latency-sensitive workloads.