A Spot Block is a former EC2 offering that allowed you to launch Spot Instances with a guaranteed duration of 1 to 6 hours without interruption, but it has been deprecated in favor of Capacity Reservations for Spot Instances and the ability to stop/start Spot Instances.
A Spot Block was a purchasing option for Spot Instances that provided a guaranteed duration of 1 to 6 hours without interruption. This feature was designed for workloads requiring a minimum runtime, such as batch jobs or data processing tasks that would be problematic if interrupted mid-execution. Spot Blocks offered a balance between the low cost of Spot Instances and the reliability of On-Demand instances for a fixed period.
AWS has deprecated Spot Blocks in favor of new capabilities including Capacity Reservations for Spot Instances and the ability to stop and start Spot Instances (introduced in 2020) [citation:8]. Today, for workloads requiring guaranteed capacity, AWS recommends using On-Demand Capacity Reservations, Savings Plans, or designing applications to be interruption-tolerant rather than relying on fixed-duration Spot capacity.