Flash memory: How the technology is getting smarter

Flash memory is getting complex — and that could be a good thing.

This technology, mainly in the form of SSDs, has brought huge benefits to datacentres as well to laptops and desktops, primarily by adding speed through increased I/O and lower latency.

To the end user these improvements bring clear performance benefits, whether that end user is at the other end of the network or at the same machine where the SSD is installed.

From the datacentre perspective, solid-state memory has enabled storage managers to add another tier to their existing two-, three- or four-tiered models. Such models have been created to contain the costs of buying high-performance storage for all data, reserving it instead for the data that benefits most, usually databases and other transactional data.

The rest, such as Windows shares, tends to live on cheaper, slower storage, where an added wait of a few milliseconds is barely noticeable, if at all.

Flash memory has also enabled applications that could hardly have existed before. While flash memory vendors are eager to tell us about implementations of desktop virtualisation, the reality is that few installations of any size are fully up and running.

They say flash memory will help to change that, as its performance profile enables the high I/O demands of virtual desktops now to be met without breaking corporate piggy banks.

That's all very well, but you can only fully reap the benefits of new technologies if they're properly integrated with existing systems, and if they're directed towards business processes rather than just being faster.

Flash vendors are moving in this direction, not just because potential customers are asking for it but also to help differentiate themselves.

For example, one vendor of in-server flash memory storage, Fusion-io, specialises in flash memory installed inside the server, on the PCI Express bus, where it acts as a super-fast storage drive. It has recently announced software that allows server-side flash storage — and therefore datasets — to be shared across servers.

According to company spokesman Gary Orenstein, it speeds large jobs such as media transcoding and database transactions because its 6GBps bandwidth can return data to the server within 50-100 microseconds.

In relation to connectivity work over Fibre Channel or InfiniBand, Orenstein said: "Normally the SAN isn't the bottleneck, so most customers can just attach this system to their FC network."

Others suppliers, such as WhipTail with its Accela flash appliance, are focusing on developing technology that helps accelerate the specific read-write patterns of individual applications, which is a hard problem for applications that do more writing than reading, such as databases and VDI.

So while flash memory makes everything go faster from an end user's point of view, from the datacentre storage manager's point of view, it's a technology that needs careful integration with existing systems. If not, it could just end up being an unjustifiable expense.