Why All Flash Arrays and SDS Are Re-defining Storage

"Just as what happened about eight years ago when we moved from tape to disk, one can expect the same thing while moving from disk to flash"

Storage technologies have been undergoing a constant evolution, but the centerpiece of all this action has always been the humble hard drive. With their rotating spindle and magnetic platters, hard drives gradually gained an edge over tape drives to become the preferred choice for backup. They were used in all sorts of storage devices, be it NAS, SAN, JBOD, or any other storage environment. There has been a constant development in hard drives to increase their capacity and improve performance, but the core technology always remained spindle and platters.

Future Data Centers to Have All Flash Arrays

Not anymore, because the same level of development is now happening around flash based drives. According to Joybrata Mukherjee, “One of the big areas in storage today is flash arrays. It’s the way to go. Just as what happened about eight years ago when we moved from tape to disk, one can expect the same thing while moving from disk to flash”. His view is that flash based systems are more resilient and offer very stable performance, so there’s no reason why customers shouldn’t really opt for them”. In fact, he feels that future data centers will have all flash arrays.

The indication for this is the fact that companies today are mostly investing in hybrid arrays containing both disk and flash. “Right now companies are using flash only for their high performance workloads, meaning there hasn’t been complete acceptance of all flash arrays yet, except by a few large organizations like large Internet companies who have a lot of transactions, or applications like OLTP, and large VDI deployments” said Joybrata. But he feels that all future expansion will be on all flash arrays. “But by next 2 years, all major enterprises will have shifted to all flash arrays”, he added.

Applications are already ready for flash, with large companies like SBI using SSDs in their SAN for last 8-9 years. CIOs therefore know and understand all flash arrays, but are cautious because it’s not an easy decision to change their mission critical applications. “Most of them don’t really want to be the first movers, and would like to first see what sort of resilience and uptime it provides, among other factors before taking the plunge” he added. Another factor that will contribute to greater acceptability of All Flash Arrays is that their price has really come down over the past three quarters and will continue doing so in the future. It has reached a level where if you do a 4 year TCO on all flash arrays, you’ll realize how much they can really save on power consumption in a data center, over traditional disk based arrays.

SDS Catching Up Fast

The other storage evolution that’s taking shape, according to Joybrata, is software defined storage (SDS). He feels that though it’s still 3-4 steps behind all flash arrays in the evolution cycle, but it’s catching up fast, and one of the reasons for that is that the market knows what their workloads are. “We’ve done a few trials, like one with a large bank having about 3000 branches across the country to see how SDS/virtual storage arrays can be used across branches, and the kind of branch application response they’ll deliver”, he said.

Nevertheless, this is just the beginning of the SDS journey, but Joy feels confident that they’ll have many more test cases in another six to twelve months to show the value of SDS. Once this is done, it will help increase their adoption.

One key challenge enterprises face while migrating to SDS is that their storage infrastructure lies mostly in silos. So moving to a software defined storage architecture that consolidates everything is a huge challenge. This is possibly because vendors in the past have introduced so many different storage architectures in the market. So there would be one architecture for high end SAN, and a different one for NAS, and yet another one for flash in the same enterprise. “In all, there could be at least 8-9 different storage architectures implemented in an enterprise, so our story to CIOs is that we can collapse all such siloes under one uniform architecture, be it SAN, NAS, or even the latest all flash array”, added Joybrata. One of the reasons for this is that in a distributed storage environment, with installations in branches and remote locations, SDS helps by allowing you to manage it all centrally.