Architecture and Management
One of the keys to Micron's success with the P320h is the lack of bridging chips or hardware. The architecture combines all 64 placements of NAND into 32 channels, with no intermediary SSD controllers or RAID controllers. Several types of solutions on the market today have SSD controllers onboard the PCB and these in turn feed the RAID controller. Micron simplifies the design, minimizing the amount of hardware and maximizing latency and throughput performance to the controller.
The Micron-developed ASIC (Application Specific Integrated Circuit) controller provides an embedded ATA host bus adapter, a host/flash translation later, flash maintenance, channel control and a NAND RAID (RAIN) protection scheme. This streamlined architecture also dispels clunky non-native interfaces, which tend to become the slow point in many solutions. Translating protocols from SAS or SATA to PCIe tends to incur latency penalties that are not a factor with the P320h, which enjoys native PCIe technology.
The IDT 89HF3208 controller is a 1517 pin FCBGA (Flip Chip Ball Grid Array) which handles 32 channels, supporting four-way interleaving up to 128 NAND dice. The functions of the SSD are all handled on-die to minimize host overhead.
The P320h features three interrupt coalescing settings to allow users to tailor the SSD to their workloads. This allows issuance of more than one I/O during each interrupt to boost performance in heavy workloads. This feature leads to some interesting results later in the review when the drive is under very heavy load. An additional coalescence setting provides more optimized performance for a low QD environment.
The RealSSD P320h is managed through the RealSSD Manager utility. This easy to use GUI makes management of the drive very easy. The RSSDM simplifies many processes such as secure erasing, temperature monitoring, firmware updates and coalescing settings. The utility also provides device monitoring and allows users to graph the read and write throughput and temperature. There is also access to the SMART data for the drive, which allows users to predict the expected lifetime of the device. Micron also provides a CLI utility, which is handy for those that are using servers without graphical interfaces.
Many of the competing application accelerators on the market do not include such refined management tools, though this one does lack remote management capability it still takes a big lead over many of Micron's competitors.