For months SandForce has been telling me that the market is really going to get exciting once its next-generation controller is ready. I didn’t really believe it, simply because that’s what every company tells me. But in this case, at least based on what SandForce showed me, I probably should have.
What we have today are the official specs of the second-generation SandForce SSDs, the SF-2000 series. Drives will be sampling to enterprise customers in the coming weeks, but we probably won’t see shipping hardware until Q1 2011 if everything goes according to plan. And the specs are astounding:
We'll get to the how in a moment, but let's start at the basics. The overall architecture of the SF-2000 remains unchanged from what we have today with the SF-1200/SF-1500 controllers.
SandForce’s controller gets around the inherent problems with writing to NAND by simply writing less. Using real time compression and data deduplication algorithms, the SF controllers store a representation of your data and not the actual data itself. The reduced data stored on the drive is also encrypted and stored redundantly across the NAND to guarantee against dataloss from page level or block level failures. Both of these features are made possible by the fact that there’s simply less data to manage.
Another side effect of SandForce’s write-less policy is there’s no need for an external DRAM to handle large mapping tables. It reduces the total BOM cost of the SSD and allows SandForce to charge a premium for its controllers.
These are the basics and as I mentioned above, they haven’t changed. The new SF-2000 controller is faster but the fundamental algorithms remain the same. The three areas that have been improved however are the NAND interface, the on-chip memories, and the encryption engine.