ZRAID: Leveraging Zone Random Write Area (ZRWA) for Alleviating Partial Parity Tax in ZNS RAID

The Zoned Namespace (ZNS) SSD is an innovative technology that aims to mitigate the block interface tax associated with conventional SSDs. However, constructing a RAID system using ZNS SSDs presents a significant challenge in managing partial parity for incomplete stripes. Previous research permanently logs partial parity in a limited number of reserved zones, which not only creates bottlenecks in throughput but also exacerbates write amplification, thereby reducing the device's lifetime. We refer to these inefficiencies as the partial parity tax.