Seagate ST3146855LC Optimizing Storage with SAS: Beyond the 10K Compromise (72 - Page 2

The 15K Advantage: More Performance, More Capacity Storage Configuration: 2U w/12 3.5-Inch Disc Drives Online (SAS) Online (SAS) IOPS per Drive IOPS,Total Nearline (SATA) Capacity, Total Nearline (SATA) Cost/GB (est.*) 15K SAS Advantage 5 - 15K SAS Drives (146GB) 7 - 7200 SATA Drives (400GB) 15K SAS/Nearline SATA vs. 10K SAS/Nearline SATA 55.1 275.5 2800GB $1.00 11% More Online Performance, 17% More Nearline Capacity 6 - 10K SAS Drives (146GB) 6 - 7200 SATA Drives (400GB) 5 - 15K SAS Drives (146GB) 7 - 7200 SATA Drives (400GB) 6 - 10K SAS Drives (146GB) 6 - 10K SAS Drives (300GB) 41.4 248.4 2400GB $1.00 15K SAS/Nearline SATA vs. All 10K SAS 55.1 275.5 2800GB $1.00 41.4 248.4 1800GB $4.00 (SAS) (SAS) 11% More Online Performance, 56% More Nearline Capacity at 75% Lower Cost Test results from IBM xSeries 336 with EXP 400, general transactional workload, RAID 5. *Source CDW, August 2005. Table 1. 15K SAS delivers more performance and capacity Should more nearline storage be required, a combination of four 15K SAS/8 SATA drives would yield moderately lower IOPS (220.4) than the reference 10K/SATA configuration, but offer 33 percent greater nearline capacity (3200 Gbyte). Conversely, when online speed is the top priority, a mix of six 15K SAS/6 SATA drives results in 33 percent higher IOPS (330.6) than the 10K reference system, while providing the same nearline capacity. For IT managers seeking to address both online and nearline applications with 10K SAS drives, the associated performance and capacity figures are even more eye-opening. Not only does the 15K SAS/Nearline SATA combination yield higher online IOPS than an all-10K SAS solution, it also delivers 56 percent more nearline capacity at 75 percent lower cost. Regardless of the 10K SAS configuration under consideration, the net result is that 15K SAS solutions provide significantly lower total cost of ownership (TCO). Delivering greater performance with fewer drives than its 10K counterpart, 15K SAS reduces storage costs such as infrastructure, IT maintenance support, data center footprint, and power and cooling. And it is this total cost of ownership, not individual drive prices, that ultimately determines the cost-effectiveness of a storage solution. Improving Storage Efficiency In the late Nineties enterprise data was largely transactional, so it was only natural to employ costly high-performance drives for virtually all disc-based enterprise storage applications. However, as time passed and the quantity of reference data (including safety copies of mission-critical files) mushroomed, it became clear that more targeted, cost-effective storage was needed. Fortunately, such high-efficiency storage has now become a reality. Purpose-built disc drives are widely available to ensure every application-from online transactional duties to nearline bulk storage tasks-can be addressed with the optimal blend of performance, reliability and cost-effectiveness. SAS is leading this movement, its compatibility with SATA ensuring unprecedented freedom to specify and consolidate the most appropriate storage devices for a broad range of applications. Beyond the cost savings of utilizing a common infrastructure, SAS/SATA compatibility promotes further efficiencies by enabling IT managers to: • Fine-tune storage cost/performance for a given application with the optimal blend of SAS and SATA drives • Fully exploit SATA's cost/GB economies without compromising enterprise management and reliability requirements • Increase storage capacity while maintaining application requirements 2