While I don't want to write just about news items, I think the most recent announcement from Seagate is very noteworthy because of the implications.
Seagate just announced it reached an areal density of 625 Gbit/in^2, which correlates to about 1 TB per platter for 3.5" drives. It announced that it should have platters like this available in the middle of this year. What this means is that Seagate can reach 3TB drives with just three platters, reducing cost and complexity.
Alternatively, using these platters Seagate can easily make a 5TB drive whenever it wants. It just uses five of the new 1TB platters in a 3.5" drive chassis and bingo--5TB drives. This could easily give the company a technical advantage over anyone else, or it could just hold off and let the community adjust to 4KB sectors that are coming with larger drives, and then introduce larger drives.
There is one implication of the larger hard drives that should be addressed--that is the increasingly disparity of the capacity between SSDs and conventional hard drives. There are SSDs that have large capacities but are fairly expensive (for example, 1TB drives). The mainstream SSD drives are slated to maybe reach about 400GB to 500GB this year but will likely still be fairly expensive (perhaps just under $1,000). In the meantime, we could easily have 5TB 3.5" drives. So the disparity between SSDs and conventional hard drives is creating a wider gap between capacity (conventional hard drives) and SSDs (performance). I think this disparity is going to increase the importance of using SSDs as high-speed data tiers coupled with huge capacity hard drives or perhaps the importance of using SSDs for caching block devices.
Keep an eye out--this could accelerate change in the storage hardware world.
posted by: Jeff Layton