DapuStor's new J5060 SSD takes a dual-mode approach to QLC NAND. Instead of running the entire drive as slow-but-dense QLC, it permanently carves out a portion of the flash to operate in pSLC (pseudo-single-level-cell) mode. That reserved region acts as a fast write buffer, while the rest remains high-capacity QLC for storage.
The trade-off is explicit: the drive gives up between 6% and 20% of its raw QLC capacity to create the pSLC area. For example, a 30.72TB model sacrifices 4TB of QLC to yield 800GB of pSLC flash. In return, random write speeds jump by more than 7x compared to a pure QLC configuration, according to Tom's Hardware.
This design addresses a common pain point of QLC SSDs—poor write performance under random workloads. By making the pSLC region permanent rather than a temporary cache, DapuStor ensures consistent fast writes without the wear-leveling or data-migration overhead of dynamic SLC caching. The trade-off is a meaningful capacity loss, but for workloads that need both high density and responsive writes, the J5060 offers a clear split between speed and space.