Correct the article, Netlist is American
Netlist is not Canadian.
"It partially uses NVault NVDIMM (non-volatile DIMM) technology licensed from Netlist, a "Canadian" business."
FlashDIMMs can turn Nimble Storage arrays into supercharged systems, shortening IO latencies and speeding overall IO. These commodity-based systems use flash as an extension of memory with lower-than-PCIe-flash card latencies, due to them having DIMM-level access to the CPU-memory bus inside their server/controllers. It …
This is such silly Marketing tripe. Anyone with elementary experience knows that NVMe is NEVER the bottleneck - not for any form of latency or bandwidth. To use DIMM-Flash in this way requires the same block layer software stack, so no gain there. There could be gains for cost and density, but please stop the FUD on Flash-DIMMs that's being spoon fed by the vendors.
Nimble employee here...
I sort of have to agree with the AC above calling this marketing tripe - sort of. The NV layer only becomes a bottleneck at extremely low latency rates. The change from the PCIe based NV layer to the NVDIMM saw write latency on Nimble reduced from ~.67 ms to ~.33 ms latency. The previous gen was already great for performance. The .34 ms reduction is not going to have much impact for most applications as it was already screaming fast - if you have an application that can benefit from a write latency improvement measured in microseconds - well, you're an interesting bloke, or at least have an interesting app.
The switch to NVDIMM did free up a slot on the PCI bus, allowing now up to 6 ports per controller - 10 GbE or 16 Gb FC. That was more impactful. But the switch came at the same time the new platform launched, taking Nimble from Nehelam family processors all the way to Ivy Bridge. Other internal changes enabled by the new chipset had an impact in the latency reduction as well.
In answer to the question - "Is it enough?" - well, no it isn't. But couple the NVDIMM with new micro-architecture and chipset features, more cores and RAM, and Nimble did manage to reduce latency and increase I/Ops to over 120,000 where the previous generation topped out about 70,000. So, yes, the controller is the bottleneck, not the NV layer.
Nimble never bothered doing a special press release regarding the change to NVDIMM in the second generation - it's just one component. A competitor saw fit to announce that they were planning to make a change to NVDIMM and tried to make a big splash with it. Nimble employees like myself felt compelled to point out that this was not a new innovation on the competitors part.
In my Marketing tripe post, Im ref. to potential benefits of Flash Dimms vs Flash SSD, eg NVMe SSD. Not NVDRAM-Dimm vs NVDRAM-NVMe where, being RAM, the PCIe does have overhead that exceeds the media. This is not true for NAND.
With Flash DIMMs, where things get wonky is with benchmark workloads that dont exceed the DRAM buffer - same with a SSD's RAM cache. The Marketing tripe from Diablo and their Flash DIMM is a total joke - the result of staged workloads.
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