RAID-optimal data placement in a hybrid solid-state drive

Flash-based solid-state drives (SSD) are widely accepted from mobile devices to enterprise storage arrays. They are best known for delivering low power consumption and high random I/O performance that far exceeds hard-disk drives (HDD). One configuration to enhance performance and reliability further is to connect multiple SSDs to a RAID controller. In this paper, we propose an intelligent, hybrid SSD that is optimized in distributed-parity RAID schemes by recognizing data-parity block sequence and placing parity blocks in higher endurance memory cells. The experimental results show that our predictive data placement extends SSD lifetime by 31% on average, compared to the history-based hot data placement.