HP StorageWorks 2/16V ISS Technology Update Volume 8, Number 7 - Page 4

ISS Technology Update Volume 8, Number 7 SSD Performance HP 3Gb/s SATA SSD read and write performance is significantly improved over first-generation SSDs, as shown in Table 1. The new SSDs are particularly appropriate for applications that require storage systems capable of performing large numbers of random reads per second. Traditionally, solutions designers have used RAID configurations with large numbers of disk drives to achieve this. Using the new HP solid state drives, a single SSD can deliver two to six times as many random reads per second (IOPs) as an entire RAID 0 array of 12 SAS disk drives. This makes the new drives ideal for read-intensive, high-IOPs applications that do not require the large storage capacities that RAID configurations can offer. Table 1. Performance comparison of SATA/SAS drives with SSDs for servers 6 Gb/s SAS drive 1st generation HP SATA SSDs 2nd generation HP 3Gb/s SATA SSDs Class Enterprise Midline Midline HP SAS SSDs (preliminary) Enterprise Interconnects 6 Gb/s SAS-2 1.5 Gb/s SATA 3.0 Gb/s SATA 6 Gb/s SAS-2 Dual Port Write performance sustained throughput Write performance random IO/s Read performance sustained throughput Read performance random IO/s 150 MB/s @ 64 KB 285 (4 KB, Queue=16) 90 MB/s 340 (4 KB, Queue=16) 50 MB/s 100 100 MB/s 4300 180 MB/s 5000+ 230 MB/s 20,000+ TBD TBD 560 MB/s Up to 100,000 HP SSD futures The new HP 3Gb/s SATA SSDs are the first SSD products designed to operate across most of the ProLiant server line. They continue to use the more robust single-level cell NAND flash technology and are suitable for use in Midline (MDL) drive environments where unconstrained workloads and a 100% duty cycle are not required. The NAND flash memory used in SSDs has a limited life cycle for writes. Although advanced techniques such as wear-leveling and over-provisioning are used to help overcome this, HP 3G SATA SSDs are still better suited for read-intensive environments where writes are 30% or less of the total IO load. SSD technology is still rapidly evolving. HP hopes to introduce its first Enterprise class SAS SSDs in 2010. These drives will be engineered for unconstrained read and write workloads and 100% duty cycles. This will match the basic reliability characteristics of Enterprise class disk drives while providing the IO performance advantages of SSDs. HP may also introduce server SSDs based on multi-level cell NAND flash memory. These products will provide a solution for application environments that need higher capacity SSDs, but do not require support for unconstrained IO workloads. Additional resources For additional information on the topics discussed in this article, visit the following websites: Resource URL HP Solid State Storage www.hp.com/go/solidstate Technology brief - Solid state drive technology for http://h20000.www2.hp.com/bc/docs/support/SupportMa ProLiant servers nual/c01580706/c01580706.pdf HP ProLiant drives (including solid state drives) www.hp.com/products/harddiskdrives 4