Info Tech At CES this year, Samsung was anxious to show off the PM1633a, a massive 15.36TB SSD. It’s optimized for data center workloads and enterprise deployments, with possible alternate use cases like high frequency stock trading, storing all human knowledge from the dawn of creation to about 1500 AD, or housing the porn collection of an average college student. Today, Samsung announced that the drive is actually shipping (though the company refused to comment on our speculation regarding alternate uses for its SSD).
We now know a bit more about the PM1633a than we did in January. The drive uses SAS (Serial Attached SCSI) and combines 512 NAND flash chips all in the same 2.5-inch form factor as a standard drive. The company accomplished this feat in two stages. First, it used its third-generation 3D NAND (V-NAND), which stacks NAND cell arrays in 48 layers per IC, for a total of 256Gb per die.
It then stacked those dies 16 layers deep to create one NAND package with a capacity of 512GB. Take 32 of those stacks, slap them on a PCB, and you’ve got yourself a 16TB SSD that probably pushes the boundaries of NAND flash density further than any product we’ve seen to date.
Samsung hasn’t revealed much about the drive’s memory controller, but notes that it can sustain random reads of 200,000 IOPS and write at 32,000 IOPS. Sequential read/write speeds are both in excess of 1200MB/s. The SSD memory controller supports the 12Gbps SAS interface, and packs a massive 16GB of DRAM to act as a cache. While SSD DRAM caches are common, most of them are between 256MB and 512MB. 16GB, while reasonably proportional to the actual storage capacity, is still an awful lot of DRAM. Samsung has validated the drive to sustain a full rewrite per day — that’s 16TB of writing per day, every day. Samsung hasn’t stated the warranty terms, but claims the PM1633a’s NAND is between 2x and 10x more durable than the typical MLC or TLC NAND.
This drive isn’t going to be cheap — not given that Samsung is using multiple types of 3D technology to build it. There’s no word yet on price, though I strongly suspect this is another one of those “If you have to ask how much it costs, you can’t afford it” situations. Previous drives in this family have been up to $1000 per TB, but estimates floating around the Internet are mostly in the $5000 – $8000 range.
Drives with densities like this aren’t going to be mainstream any time soon — 3D NAND capacity will need to increase enormously before the drive can be built for consumer price points. Still, it does illustrate the potential space savings by moving silicon into three dimensions. Samsung’s PM1633a combines both 3D NAND and 3D chip-stacking to pack far more data into a tiny form factor than we’ve previously seen.