Subject: Storage | November 20, 2017 - 10:56 PM | Allyn Malventano
Tagged: Z-NAND, SZ985, slc, Samsung, P4800X, nand, Intel, flash
We haven't heard much about Samsung's 'XPoint Killer' Z-NAND since Flash Memory Summit 2017, but now we have a bit more to go on:
Yes, actual specs. In print. Not bad either, considering the Samsung SZ985 appears to offer a bus-saturating 3.2GB/s for reads and writes. The 30 DWPD figure matches Intel's P4800X, which is impressive given Samsung's part operates on flash derived from their V-NAND line (but operating in a different mode). The most important figures here are latency, so let's focus there for a bit:
While the SZ985 runs at ~1/3rd the latency of Samsung's own NAND SSDs, it has roughly double the latency of the P4800X. For the moment that is actually not as bad as it seems as it takes a fair amount of platform optimization to see the full performance benefits of optane, and operating slightly higher on the latency spectrum helps negate the negative impacts of incorrectly optimized platforms:
Source: Shrout Research
As you can see above, operating at slightly higher latencies, while netting lower overall performance, does lessen the sting of platform induced IRQ latency penalties.
Now to discuss costs. While we don't have any hard figures, we do have the above slide from FMS 2017, where Samsung stressed that they are trying to get the costs of Z-NAND down while keeping latencies as low as possible.
Image Source: ExtremeTech
Samsung backed up their performance claims with a Technology Brief (available here), which showed decent performance gains and cited use cases paralleling those we've seen used by Intel. The takeaway here is that Samsung *may* be able to compete with the Intel P4800X in a similar performance bracket - not matching the performance but perhaps beating it on cost. The big gotcha is that we have yet to see a single Samsung NVMe Enterprise SSD come through our labs for testing, or anywhere on the market for that matter, so take these sorts of announcements with a grain of salt until we see these products gain broader adoption/distribution.