Be On Time: Command Duration Limits Feature Support in Linux
Delivering high throughput and/or high IO rates while minimizing command execution latency is a common problem to many storage applications. Achieving low command latency to implement a responsive system is often not compatible with high performance. The ATA NCQ IO priority feature set, supported today by many SATA hard-disks, provides a coarse solution to this problem. Commands that require a low latency can be assigned a high priority, while background disk accesses are assigned a normal priority level.