Samsung at Flash Memory Summit: 64-layer V-NAND, Bigger SSDs, Z-SSD
by Billy Tallis on August 11, 2016 5:30 AM ESTAt Flash Memory Summit, Samsung announced their fourth generation of 3D NAND and several of the more obvious SSD upgrades it enables. Taking a page from Intel and Micron's strategy book, they also announced a new memory type and corresponding SSD product while saying essentially nothing about what the new memory actually is.
The fourth generation 3D NAND bumps the layer count up to 64, compared to the 48-layer design used by the third generation V-NAND that was announced last fall and has been slowly rolling out to their SSD products over the course of this year. So far Samsung has talked about a 512Gb TLC part, and at least initially the MLC parts will probably be made from the same die and thus have two thirds the capacity. (Samsung's second generation 3D NAND was initially available as 128Gb TLC or 86Gb MLC, with 128Gb MLC parts introduced later.) The new NAND also supports an increased interface speed of 800Mbps, which is key to reducing the performance penalty that comes from consolidating more flash onto fewer independent chips.
With a per-die capacity of 512Gb (64GB), Samsung can now put 1TB of TLC flash in a single package. This means most product lines will be seeing an increase in capacity at the high end of the range. Their BGA SSD products will be offering 1TB capacity even in the 11.5mm by 13mm form factor. The 16TB PM1633a SAS SSD will be eclipsed by the new 32TB PM1643. Likely to be further out, the PM1725 PCIe add-in card SSD will be succeeded by the PM1735 with a PCIe 4 x8 host interface.
Complementing the NAND update will be a new non-standard oversized M.2 form factor 32mm wide and 114mm long, compared to the typical enterprise M.2 size of 22mm by 110mm. A little extra room can go a long way, and Samsung will be using it to produce 8TB drives. These will be enterprise SSDs and Samsung showed a diagram of these enabling 256TB of flash in a 1U server. Samsung will also be producing 4TB drives in standard M.2 sizing.
In what is likely a bid to steal some thunder from 3D XPoint memory before it can ship, Samsung announced Z-NAND memory technology and a Z-SSD product based around Z-NAND and a new SSD controller. They said nothing about the operating principles of Z-NAND, but they did talk about their plans for the Z-SSD products.
Samsung Z-SSD is being marketed as addressing the performance gap between DRAM and SSDs. Samsung's slides during their keynote showed some performance comparisons against the PM963 NVMe TLC SSD and against an unnamed "PRAM based" solution. The logical point of comparison would be against 3D XPoint NVMe drives, but Samsung can't have real performance and power numbers on those when they're still under development by Intel and Micron. Thus the PRAM based solution Samsung refers to is probably one of their own earlier R&D efforts that didn't make it to market. The Z-SSD ties or comes out ahead on every benchmark Samsung showed, but NVMe NAND flash SSDs were missing from the power consumption comparison.
The slides stated that there will be a 1TB Z-SSD this year and 2TB and 4TB Z-SSDs next year, while the press release issued later states that more generally that the Z-SSD is expected to be released next year. The press release also states that Z-NAND "shares the fundamental structure of V-NAND and has a unique circuit design and controller that can maximize performance". Given that, the launch timeframe and capacities that are only a little lower than NAND flash SSDs, it seems that Z-NAND isn't drastically different from existing memory technologies and it may even be little more than SLC flash in disguise, trying for a comeback.
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ats - Thursday, August 11, 2016 - link
3D NAND isn't that much of a panacea. Raw cell endurance is still less than historical 40nm cell endurance.extide - Thursday, August 11, 2016 - link
3D NAND did reset that clock a bit though because they went UP in feature size.ddriver - Thursday, August 11, 2016 - link
Complete BS.SLC - 50k to 100k+
MLC - 3k to 10k
TLC - 0.5k to 1k
Process also matters, and note size shrinks the wear increases. Stacking nand dies vertically doesn't do any magic in terms of endurance, it might even decrease it a little.
revanchrist - Thursday, August 11, 2016 - link
1000X my ass, those numbers are total marketing bshit to create hype. Read this article: http://www.tomshardware.com/news/intel-micron-3d-x... and you can see that "Micron also revealed that its first QuantX SSDs would feature 25 DWPD (Drive Writes Per Day) of endurance over a five year period with the first generation of 3D XPoint. In comparison, some enterprise SSDs based on MLC NAND provide up to 10 DWPD, whereas TLC NAND SSDs provide between <1 to 5 DWPD of endurance."ddriver - Thursday, August 11, 2016 - link
Yeah, it seems optane is mostly hype, density is cr@p, performance and endurance are like 2-3x better than current MLC PCIe SSDs, nowhere near the 1000x intel claims. By the time it becomes widely avaiable, samsung will have an easy time competing with stacked SLC.fanofanand - Thursday, August 11, 2016 - link
There is a certain level of "honesty" that must be utilized in these presentations, and I'm sure Intel toed that line carefully. Typically they will say "up to" and then quote some insane number. Well maybe they are comparing it to the first OCZ SSD ever made? So in that sense it isn't BS, but it also isn't what most people would consider "honest". It's all about staying within the legal boundaries.ddriver - Thursday, August 11, 2016 - link
Even if we assume intel based their claims on some highly isolated, practically irrelevant in real world applications test, it is still highly suspicious that such tests would come with EXACTLY 1000x faster and more durable than nand, not 905, not 982, exactly 1000 for both metrics. Highly unrealistic. Also, they clearly don't have an "up to":http://www.intel.com/content/www/us/en/architectur...
It says "1000x faster than nand" and "1000x endurance of nand", there are no "up to"s. And I in turn say "total BS".
ddriver - Thursday, August 11, 2016 - link
I'd honestly be surprised and impressed if it is actually twice as good as what nand SSDs will be able to offer by that time and at that price point in real world scenarios. That would be more in line with the lazy mediocre intel we've been seeing the last several years.smilingcrow - Thursday, August 11, 2016 - link
I think the latency is going to be significantly better. There was a very recent quote supposedly from Facebook who have been testing the technology claiming very useful real world gains. Not even 10x but in real world you rarely get even 10x gains except in bench-marking tools.smilingcrow - Thursday, August 11, 2016 - link
Facebook revealed its performance results with an Intel Optane SSD prototype which tripled the number of transactions that the company achieved with a normal P3600 NAND SSD during a RocksdDB throughput test, but more importantly, Optane reduced the 99.99th percentile results (worst-case latency) by more than 10X.http://www.tomshardware.com/news/intel-micron-3d-x...