Micron's Enterprise MLC-Based SSD
True enterprise-oriented SSDs are very expensive, and the SLC (single-level cell) NAND typically used in these solid-state drives is a major reason why. SLC NAND provides high performance data access and long-term endurance in demanding enterprise I/O environments, but, as we've seen time and again, is quite costly. In contrast, MLC (multi-level cell) NAND is far cheaper, but delivers slower write speeds, fewer program-erase cycles, and higher power consumption.
Given the significant premium on enterprise-class SSDs, there's an increasing emphasis on bridging the gap between the endurance, performance, and cost of SLC- and MLC-based drives. But is it even possible to achieve the I/O performance and long-term reliability heavy enterprise workloads require using consumer-grade MLC NAND?
We all recognize the potential of fast SSDs in demanding environments, after all. But magnetic storage is still most prevalent. Most IT professionals would welcome a transition to solid-state technology if it could be made less expensive, particularly in read-heavy applications where endurance isn't as pressing of a concern.
Micron's P400e is designed specifically to satisfy that space. A near twin of the consumer-oriented Crucial m4, Micron's P400e shares the same Marvell 9174 SATA 6Gb/s controller and 25 nm MLC NAND. In fact, the two SSDs are so similar that we found ourselves wondering: what, precisely, differentiates the P400e as an enterprise-grade SSD?
According to Micron, the P400e is equipped with firmware designed for read-heavy enterprise workloads, including 28% over-provisioning and data protection via memory path error correction. The company sees this drive deployed to address a wide range of business applications where SLC-based hardware might have been cost-prohibitive in the past. This partly explains why the P400e is manufactured to a 7 mm Z-height. It is possible to install the drive in the 9.5 mm standard form factor using a shim, making it easier to deploy in 1U/2U servers and more common hard drive racks.
| Micron RealSSD P400e Specifications | MTFDDAK050MAR-1J1AA | MTFDDAK100MAR-1J1AA | MTFDDAK200MAR-1J1AA | MTFDDAK400MAR-1J1AA |
|---|---|---|---|---|
| Raw NAND | 64 GB | 128 GB | 256 GB | 512 GB |
| User Capacity | 50 GB | 100 GB | 200 GB | 400 GB |
| Sequential Read | 350 MB/s | |||
| Sequential Write | 140 MB/s | |||
| 4 KB Random Read | 50 000 IOPS | |||
| 4 KB Random Write | 7000 IOPS | |||
| Power Consumption (Active) | 2.5 W for 50 GBUp to 5 W for 400 GB | |||
| Warranty | Three years |
Like the Crucial m4, Micron's RealSSD P400e is available in four capacities: 50, 100, 200, and 400 GB. However, the P400e's performance specifications fall a bit short of most SATA 6Gb/s-equipped SSDs we test (most notably the m4 that this drive looks a lot like), rated for 350 MB/s sequential reads, 140 MB/s sequential writes, 50 000 random read IOPS, and 7000 random write IOPS.
Acknowledging that reliability is more important than the performance of what we'll call an "entry-level" enterprise SSD, Micron deliberately alters its firmware to put more emphasis on trouble-free operation. The company hopes its approach may help prevent some of the firmware-related idiosyncrasies that plagued Crucial's m4 (and indeed, many other desktop-oriented drives that see three or four updates to correct show-stopping issues).
