Toshiba offers a refined 12Gb/s product stack with a flavor for every taste. The Toshiba PX02SS offers unmatched endurance in the 12Gb/s segment, while the Toshiba PX02SM provides solid endurance and serves as the mixed-use model for mainstream applications. The PX03SN steps in to provide amazing 12Gb/s performance at a much lower price point. The two heavier-use Toshiba SSDs utilize 24nm eMLC to provide robust endurance, but the PX03SN switches to 19nm consumer-grade MLC to provide a friendlier price point. Pairing the 19nm with the same design and controller as the leading Toshiba SSDs provides blistering performance in a more economical package.
The PX03SM comes in the familiar 2.5-inch form factor, and most notably features a 12Gb/s SAS3 connection. One of the greatest aspects of the PX03SN line is found in the capacity listing. The PX03SN is available in 200, 400, and 800GB capacities in the 7mm form factor, but a whopping 1.6TB version is available in 15mm. This tremendous capacity outstrips all HDDs in the 2.5-inch form factor and provides enhanced density for small servers. Performance density is also important, and the PX03SN brings outstanding performance in a small package.
The PX03SN features 130,000/26,000 random read/write IOPS. Random speed is matched by an impressive 1,100 MiB/s in sequential read, but only 380 MiB/s of sequential write speed. The PX03SN is designed for light-duty storage and read-caching applications that are not overly dependent upon sequential write performance. These read-centric applications tend to rely more upon serving relatively static data repositories at a high rate of speed. The PX03SN also features up to 63,000 IOPS in random workloads with a 70/30 read/write distribution.
Bringing High-Availability features to a read-centric SSD is impressive. The 12Gb/s dual-port SAS provides multipath and failover capabilities, and Toshiba leverages its proprietary Quadruple Swing by Code, a layered ECC system, to provide protection for user data. Another nice inclusion on a value SSD is the power capacitors that flush data to the NAND in the event of host power loss. Toshiba covers the bases for data security compliance with available security models and support for SANITIZE instant secure erase.
For those requiring high endurance, the Toshiba series offers the PX02SM and PX02SS. The PX03SM only offers 1 Drive Write Per Day (DWPD) of endurance. Endurance measurements are measured under worst-case scenarios. The drive is filled to capacity, which significantly reduces endurance, and endurance-killing pure small-block random data is used for testing. With sequential or mixed-workloads, the endurance will likely be incrementally higher, and any spare area increases endurance. Many users manually appropriate extra spare area to boost endurance to accommodate heavier workloads. The lower price associated with MLC provides users a bit more room for endurance optimization.
Read-centric SSDs provide amazing acceleration in read-only caching applications. Server-side caching implementations boost performance of underlying disk storage in SAN/NAS and DAS environments. By only caching read data, lower-endurance SSDs deal with relatively static data sets but deliver big results. The higher capacity versions, such as the 1.6TB PX03SN, allow for plenty of dynamic adjustment of cached data if the dataset changes frequently.
The Toshiba PX03SN offers the standard five-year warranty available with most enterprise SSD products. The read-centric 12Gb/s SSD market is relatively limited as 12Gb/s makes its way into the datacenter. With no other read-centric 12Gb/s SSDs available for testing, we will compare the PX03SN to its higher-endurance brethren.