While the price can be expected to drop, Yoshida says it may not happen as fast as some people expect. Flash is not produced in the same types of quantities as spinning disks and it will therefore be hard to eliminate the price gap between SSD and hard drives, he says.

However, it is possible that flash will someday overtake hard disk drives as the primary data storage technology. "Eventually, the thought is that some sort of solid state disk will replace [spinning disk drives]," Yoshida says.

But the flash technology used in enterprise storage products today can wear down after about 100,000 writes, Yoshida notes. Vendors are trying to make flash more durable, but ultimately it may not be enough to make flash a suitable replacement for hard disks, Yoshida suggests. Other non-volatile storage technologies, such as , are in development and might ultimately prove to be more durable, he says.

Because hard disk drives are in such wide use and will be for the foreseeable future, vendors are pursuing several strategies to make them more efficient. One such strategy is striping, which spreads data across a wider pool of storage devices. Thin provisioning, meanwhile, over-allocates storage to servers, which allows faster provisioning of space to servers without actually adding more capacity.

Another important technology is a global cache, which allows multiple storage processors access to the same cache, Yoshida says. Such technology is available in Hitachi's USP V, the EMC DMX and IBM DS8000, he says.