Intel flops out 3D flash SSDs – and says they're the densest ever
SSD chip fashionistas adopt the layering system
Intel has introduced its first 3D NAND SSDs, updating three planar NVMe SSDs with four new models, and claiming to have the industry’s highest density 3D NAND.
The existing DC P3500, P3600 and P3700 products use 20nm MLC flash technology, with the P3500 and P3600 dating from June 2014 and the P3700 being introduced in September last year along with a P3608 (two P3600s in one SSD package).
The DC P3500, DC indicating DataCentre, is replaced by the P3320 and the coming P3500. The existing P3600 and P3700 get effectively replaced by the DC D3600 and DC D3700.
The highest-density claim is that the Intel/Micron floating gate cell technology has more Gb/mm2 than alternative charge-trap technology used by SanDisk and, we understand, Samsung. Whether that means the resulting chips have higher density than Samsung, the only shipping 3D NAND supplier today, is another matter.
We can’t assume that Intel’s 3D NAND chips are denser than Samsung’s V-NAND chips which are currently 48-layer, 256Gbit chips. The previous Samsung 3D V-NAND generation used 32-layer, 128-Gbit chips. Intel hasn’t yet revealed its 3D NAND chip capacity.
Neither Intel, nor its fab partner Micron, are revealing the cell lithography nanometre measurement, though it’s clearly larger than the 20nm MLC planar tech that’s being replaced. Intel does say that the P3320/3520 use TLC NAND.
Intel has provided read/write performance numbers for most of these new products but not their latency or endurance, raising a question as to whether these are not as good as those of the replaced products. (An X-IO performance note does say the 800GB D3700 supports 10 drive writes per day.)
In general, Intel says that its 3D NAND delivers ~1.3X faster read and write times. Here is a table listing the basic details of the old and new products:
New products in green rows.
The DC P3500 is replaced by the equivalent capacity DC P3320 and DC P3520 which is like a souped up P3320 although at this stage Intel is not providing any performance numbers for it, beyond saying it will have significant performance and latency improvements over the P3320:
Intel says the D3600 and D3700 are its first active/active dual-port NVMe SSDs and deliver breakthrough performance. The dual-porting enables, Intel suggests, high-availability storage controllers.
Let’s look at the numbers:
We can’t really agree with the breakthrough performance claim, not when comparing the P3600 and D3600. The D3600 has better random IO performance than the P3600 but worse sequential IO performance. The D3700 has worse random write performance and worse sequential IO performance than the P3700, surpassing it only with random read IO.
The P3320 is slower than the P3500 and the P3520 will likely be equivalent to the P3500 or slightly faster. Intel says these drives offer the best IOPS value. Intel is positioning the P3320 for read-intensive, warm storage, making it sound like a flash equivalent of nearline disk storage. The P3520 is aimed at online and hyper-converged system use cases.
Intel claims that these two new SSDS have up to 98 per cent of all IOs sharing the same performance characteristics and that their performance degrades by five per cent or less over their life.
X-IO Technologies has provided some performance data* comparing SAS SSDs with the D3700 product.
That looks good but it us not an apples to apples comparison, comparing, as it does, NVME SSDs against SAS ones.
Clearly X-IO has new updated ISE and iglu products coming that use the DC D3700 SSDs.
Intel is not delivering capacity upgrades with these new SSDs, and the performance improvements are only for random reads and writes, not sequential IO, and not that impressive; so why bother? We imagine that the 3D NAND product is, or will be, cheaper to produce than the equivalent capacity planar product, and that second generation 3D NAND will bump up capacities, perhaps by a factor of two or three.
These 3D flash SSDs are Intel’s first shot in what will be a hotly-contested struggle. Let’s see what WDC/SanDisk and Toshiba produce and if they and Intel can catch up with Samsung capacity-wise. ®
*X-IO storage array system using Xeon E52699v3 with 40 x Intel DC D3700 10 DWPD 800GB versus storage array system using Xeon E52699v3 with 40 x SAS 10 DWPD 400GB SSDs. Test -8K transfer with 80/20 Read/Write workload on QD 1,2,4 accessing 1 volume on the shared storage array. Measurements taken on IOMeter.