Flash flood: when smart storage teaches virtual machines to swim

In such an environment, there is a very simple relationship between the application and the storage being used. In virtualised environments, you have the storage shared across different applications. People call this the I/O blender where everything is mixed up together. It makes it hard to find out whether applications are interfering with each other. In contrast, we basically restore the very simple relationship between the application and the storage using it. You can then see what's happening in your SAP application, or in your VM. That's the visibility aspect.

TRP: How does it learn and adapt?

KH: Because you have these virtual machines sitting on the same storage, they can interfere with one another, which is what people call the "noisy neighbour" problem - in other words - you're running slowly because your neighbouring VM is interfering with you. We provide each VM with its own "swimming lane", where in your swimming pool you're isolated from the rest. In our environment, we provide that same logical swim lane, meaning you don't interfere with other applications in the same system.

You may have thousands of virtual machines running in the same system, so this isn't something you can really do manually - you need the technology to help. Some of our PhDs spend their time getting the control algorithms in software to enforce those swim lanes where you have what people call "performance isolation". We can learn about the workloads running on the system and then we adapt and change the resource allocation - a bit like an operating system that's running on the storage system. This all happens automatically, and everything is tuned automatically, so you don't need to do a lot of manual interference.

TRP: How can this help reduce total cost of ownership over time?

KH: There are two cases. The first is capex - saving money in terms of how much, per VM, it costs you. In our case, the cost of a virtual machine for storage is typically in the $50 - $60 range for a desktop, for example. One of the things that's most remarkable is how much time and operational complexity it saves you.

For example, a traditional storage system may take you a couple of days of professional services to configure. Our environment is literally installable within 15 minutes by somebody who's not an expert. The problem that I alluded to earlier, of diagnosing performance problems, can take days or even weeks to diagnose with a lot of finger pointing involved between different teams. Within our environment that's do-able within seconds, so that's a huge deal.

Another aspect is replication, cloning and data management. We do that at the virtual machine level, so you can do it right down to individual virtual machines. The typical planning process for replication can take days in the best case, whereas we can do it in a few minutes and change it very easily after that. Also, while it's complex internally, people that are completely non-experts can use the environment, so it's a radically different level of simplicity. And people like it when things are simple.

TRP: Is it inevitable that we're moving toward an all-flash future?

KH: I think so - over time. But it's all down to economics. We could do a comparison with the use of disks on laptops, which appeared on smaller, more expensive systems as a boot disk, rather than a main storage disk. I think it's going to take a while. People are not prepared to pay for something that's sports car-level, but we see over time that it will become more significant.