Kioxia announced plans to release enterprise-class PCIe 5.0 SSDs based on second-generation XL NAND flash memory at the China Flash Market 2023 conference. These drives will be able to deliver sequential write speeds of up to 13.5GB/s.
The PCIe 5.0 SSD standards presented to date, according to their developers, are capable of providing sequential read speeds of up to 12-12.5 GB / s, and most models are completely limited to 10 GB / s. Future Kioxia drives will be up to 2.2 times (118%) faster than their PCIe 4.0 interface predecessors. They also offer sequential write speeds of up to 9.7 GB/s.
It should be noted that the performance of SSD in random writes and reads of 4KB blocks is more important for enterprise customers. The new Kioxia drives offer performance of up to 3M IOPS on such reads and up to 1.06M IOPS on writes. The new drives will have a read/write latency of 27 ns, slightly lower than the previous generation SSDs of 29 ns.
Both high line speeds and excellent performance in random operations are due to the use of XL NAND memory. This memory was created to compete with the very fast Intel Optane flash memory, but it works on a slightly different principle. It is based on BiCS 3D NAND flash memory, but works with fewer layers per cell – in MLC mode (two bits per cell). Second-generation XL-NAND has increased the maximum number of blocks that can be serviced simultaneously, resulting in higher throughput.
Kioxia believes that PCIe 5.0 and CXL 1.0 will remain the main I/O interfaces for enterprise SSDs until at least 2025. In 2026, the first enterprise-class PCIe 6.0 SSDs are expected to deliver twice the throughput of PCIe 5.0.