The All Flash Storage Array - Should You Go All In?
I recently wrote a blog, The All Flash Array – To Buy or Not to Buy, which addresses a question I often hear from clients—should they go all flash?
Here are some of my thoughts:
The performance requirements for most workloads don’t require flash. For the small subset that do, a small amount makes sense. A hybrid approach with flash and spinning disk should do the job.
The price for flash continues to plunge, so there’s a real sense that throwing low-latency, high-IOPs flash at workloads will end all performance concerns. Enterprise vendors are ideally looking for customers making a three-year investment. Customers, on the other hand, more often would prefer to squeeze five years out of their enterprise arrays. They don’t want to make a choice that paints them into a corner down the road.
Even the smallest of organizations are seeing massive growth in capacity data. Most of that data is idle, and it’s hard to see how buying flash that will hold idle data ever makes economic sense. When you dig into the workloads of an SMB or medium enterprise customer, there’s a subset of really active data. Perhaps moving some or all of their VMware datastores to flash right now makes sense. Or if they have key databases that can benefit from throwing higher performing hardware at the problem. But again, this gets those customers into a hybrid environment rather than a true “all-flash” data center.
In fact, a storage array will improve its throughput by nearly 80% and reduce the response time by 30%, just by adding 1TB of flash to an existing 80 TB high-performance HDD storage pool. You’d have to add 140 additional high-performance HDDs to even come close to the effects of this cache. You’d also have to add 120% more cost to the solution and find 125% more rack space and extra power.
Of course, HDD isn’t going away altogether, at least not anytime soon. You should still use low-cost, slower SATA HDD for the bulk of your mass storage needs. But rather than thinking of flash as an expensive technology on a cost-per-gigabyte basis, consider it a bargain in terms of cost-per-IOPS.
When required, flash delivers high performance cost-efficiently. Flash offers organizations the highest possible performance from their servers, effectively capturing the full return on their server investment. So wherever performance is an issue, consider using flash as a way to improve performance while accommodating your company’s budget.
As I say in my blog…
This may be an entirely different discussion towards the end of 2015, but customers making decisions right now are finding benefits from mixing some flash storage into a larger environment dominated by spinning media.