0 0

Flash Revolution, Part 3: Intelligent Flash-based Products

In Part 1 of our series of flash storage, we looked at disk-based products using bolt-on flash as a cache. These systems still access disk in their basic data paths and cannot take full advantage of flash performance. In Part 2, we looked at flash-based products, which are designed to fully leverage flash. Flash-only products have very good IOPS but are expensive and lack management features, making them incomplete solutions for enterprise applications. Fully exploiting flash performance — while eliminating the limitations and high costs of flash-only products — requires a more intelligent approach, which is the topic of this post.

 

Figure 1: Intelligent flash-based products use a combination of flash and hard disk to achieve a 99% flash hit rate, providing sub-millisecond performance more efficiently than flash only arrays.
Figure 1: Intelligent flash-based products use a combination of flash and hard disk to achieve a 99% flash hit rate, providing sub-millisecond performance more efficiently than flash only arrays.

 

Intelligent flash-based products use a combination of flash and hard disk, but apply techniques such as inline deduplication, compression and working set analysis to service nearly all IO from flash (Figure 1). Most data evicted from flash is snapshots, replicas, unused applications, powered-off VMs and other very cold data. Unlike flash-only products, you can fill 100 percent of the useable flash without worrying about running out of space and having your applications come to a screeching halt. Intelligent flash-based products achieve sub-millisecond flash latencies, and are operationally far simpler and more cost-effective than flash-only products (Figure 2).

Figure 2: In intelligent flash-based storage systems, all writes are committed to flash, and 99% or more of reads are from flash. Disk writes only occur when cold data is evicted to disk and don't impact application performance.
Figure 2: In intelligent flash-based storage systems, all writes are committed to flash, and 99% or more of reads are from flash. Disk writes only occur when cold data is evicted to disk and don't impact application performance.

 

Given that many application management problems today originate from storage, flash combined with application-awareness allows intelligent storage systems to not only simplify storage management, but applications and the overall IT infrastructure. So why hasn’t this been done before? Prior to the advent of flash, mechanical disk-based systems were too complex to support a high level of intelligence. It would be like trying to build a personal computer using vacuum tubes. The huge leap in flash performance, at last puts intelligent storage within reach.

Figure 3: Storage systems often incorporate flash in to an existing disk-based architecture, using it as a cache. This creates additional complexity and still has performance limitations. Flash-only architectures deliver performance but still require a disk tier for cold data. Intelligent flash architectures are built around flash, but can use disk as an integral part of the system to provide cost-effective data and performance management.
Figure 3: Storage systems often incorporate flash in to an existing disk-based architecture, using it as a cache. This creates additional complexity and still has performance limitations. Flash-only architectures deliver performance but still require a disk tier for cold data. Intelligent flash architectures are built around flash, but can use disk as an integral part of the system to provide cost-effective data and performance management.

Future of Enterprise Storage

Although it is easy to think of flash as simply faster storage, it can offer far more (Figure 3). We have eliminated a key mechanical barrier to scaling computing systems. Computation, communication and — finally — storage will now scale with improvements in semiconductor technology. Consider that when transistors replaced vacuum tubes, we got much more than merely compact radios. We got more powerful and more intelligent systems. Similarly, flash is a technology with potentially profound impact when properly harnessed: intelligent products that are far simpler and far more powerful. It automates many of the tough but tedious problems such as configuration, management, efficiency and performance barriers that waste enormous amounts of system administrator effort.

Simple, intelligent, fast: This is the future of enterprise storage.

Previously in the series: Flash Revolution, Part 2: Flash-based products 

Temporary_css