To bridge the gap, FlashStore “sits between a hard drive and RAM, acting as a
high-speed holding area for frequently used data.”

Using flash in conjunction with other types of storage isn’t new in itself.
Vendors that sell such technology call it tiered storage, and say it maximizes
cost-effectiveness of storage by putting valuable, frequently accessed data on
high-priced, faster tiers, and less valuable, less frequently accessed data on
lower-cost, slower tiers.

But Microsoft says it’s added a couple of other enhancements. “FlashStore is
designed to eliminate random writes,” Microsoft says. “It organizes data in a
log structure on flash so that new data sent to flash does not lead to random
writes and, hence, is not subject to garbage collection by the device.”
FlashStore also uses a specialized RAM index to access data from flash in a
way that reduces usage of RAM.