This paper was written and submitted by NetApp and is being republished with permission.
Flexible Choices to Optimize Performance
Mark Woods and Amit Shah, NetApp
November 2008 | WP-7061-1008
Solid state drives (SSDs) based on flash memory are generating a lot of excitement. This enthusiasm is warranted because flash SSDs demonstrate latencies that are at least 10 times lower than the fastest hard disk drives (HDDs), often enabling response times more than 10X faster. For random read workloads, SSDs may deliver the I/O throughput of 30 or more HDDs while consuming significantly less power per disk. The performance of SSDscan reduce the number of fast-spinning hard disk drives you need in a storage system.Fewer disk drives translates into significant savings of power, cooling, and data center space. This performance benefit comes at a premium; flash SSDs are far more expensive per gigabyte of capacity than HDDs. Therefore SSDs are best applied in situations that require the highest performance.
The underlying flash memory technology used by SSDs has many advantages, particularly in comparison to DRAM. In addition to storage persistence, these advantages include higher density, lower power consumption, and lower cost per gigabyte. Because of these unique characteristics, NetApp is focusing on the targeted use of flash memory in storage systems and within your storage infrastructure in ways that can deliver the most performance acceleration for the minimum investment.
We are implementing flash memory solutions using SSDs for persistent storage, and we will also use flash memory directly to create expanded read caching devices. Caching can deliver performance that is comparable to or better than SSDs. Because you can complement a large amount of hard disk capacity with a relatively modest amount of read cache, caching is more cost effective for typical enterprise applications. As a result, more people can benefit from the performance acceleration achievable with flash technology.
You get even more flexibility and value from flash technology by combining it with the NetApp® unified storage architecture, which enables you to leverage your investment in flash memory to simultaneously accelerate multiple applications, whether they use SAN or NAS. Storage efficiency features such as deduplication for primary storage further increase your power, cooling, and space savings.
This white paper is an overview of NetApp’s plan to deliver SSDs (both native and virtualized arrays) plus flash-based read caching and of our ability to further leverage both of these technologies in caching architectures. Selection guidelines are provided to help you choose the right technology to reduce latency and increase your transaction rate while taking into consideration cost versus benefit.