Caching And Tiering: Intel Optane Memory H20 and Enmotus FuzeDrive SSD Reviewed
by Billy Tallis on May 18, 2021 2:00 PM EST- Posted in
- SSDs
- Storage
- Intel
- SSD Caching
- 3D XPoint
- Optane
- Optane Memory
- Tiger Lake
Conclusions
Advanced storage configurations involving multiple drives and intelligent storage management software have never quite been able to catch on as a mainstream solution. Simple single-drive configurations remain the default for the overwhelming majority of PCs, and where two or more drives are used, they are often treated as separate volumes with data placement handled manually by the user. The allure of more advanced storage systems with caching or tiering functionality is that they can mix fast and expensive storage with slow cheap storage, in the hopes of providing the best of both worlds—and manage it automatically.
Intel and Enmotus are two of the many vendors who have been pursuing those goals for years. Their latest solutions are adapted to a PC market dominated by notebooks and no longer willing to accept mechanical hard drives in those notebooks. With so many systems now offering just a single M.2 slot, these companies had to get creative in order to fit two dissimilar drives into the system.
For both the Intel Optane Memory H20 and the Enmotus FuzeDrive SSD, the big, slow, cheap storage technology of choice is now QLC NAND. On its own, QLC NAND can make for a decent entry-level drive that offers adequate performance and endurance for most PC use cases. The challenge for these more advanced solutions is to offer a meaningful improvement over baseline QLC SSDs, while not introducing too many new downsides in cost and complexity.
Intel's solution features a morsel of their 3D XPoint memory, providing unbeatable random read performance but unimpressive write speeds. It's nice to see that they've slightly improved the cache performance and they're no longer trying to present a mere 16GB as an adequate cache size, but even the 32GB offered in both capacities of the Optane Memory H20 is rather limited. A clean OS installation and just a handful of applications quickly outgrows this cache size, so every user will have to contend with a significant portion of their workload being uncached or causing cache thrashing. Since QLC NAND is still much faster than a mechanical hard drive, the consequences of a tiny cache aren't a showstopper, and in practice the cache does provide real performance benefits, accelerating many aspects of everyday usage beyond the performance that a single high-end NAND flash SSD can offer.
Enmotus is a software company, so they don't have any special hardware technology like Optane to use. Their FuzeDrive SSD is a clever re-purposing of mundane hardware: transforming a 2TB QLC SSD into a ~1.6TB device with a dedicated 128GB of SLC NAND. That SLC may not have latency as low as Intel's 3D XPoint memory, but having four times the quantity gives Enmotus a lot more flexibility in how to use the fast storage. That fits well with their software's strategy of tiering rather than caching, allowing hot data to be more or less permanently resident in the fast storage. While the FuzeDrive SSD can't match all the performance benefits of Intel's Optane caching, their solution probably provides more improvement to write endurance, and it too provides a real step up from QLC performance.
Since both the SLC and QLC in the FuzeDrive SSD are managed by the same controller ASIC, Enmotus also avoids the awkward bottlenecks of the Optane Memory H20's more literal split between the two halves of the drive. Aside from a tiny bit of driver overhead, there's hardly any performance downside for the FuzeDrive relative to an ordinary QLC SSD.
Not only do the Intel and Enmotus solutions differ in their technological approach, they also have different business models for targeting consumers. Intel's Optane Memory H20 is an OEM-only drive; it can only be acquired pre-installed in a new PC (usually a notebook). This ensures that the software portion of the storage solution will be delivered to end users pre-configured, removing the most significant barrier to adoption. It's always hard to get clear price signals for OEM drives, but systems similar to our HP review unit are currently offering the older Optane Memory H10 as build-to-order options for the same price as a pure NAND-based SSD of the same capacity (presumably using TLC NAND). Assuming the Optane Memory H20 replaces the H10 without raising those prices, that's very competitive—at least, by the standards of PC OEM storage upgrades.
Enmotus has been pursuing OEM deals as well, but they're also selling the FuzeDrive SSD through retail channels to consumers for aftermarket storage upgrades and PC building. Their current pricing is in line with top of the line consumer SSDs, which sounds like an awful lot for what is basically entry-level hardware. The clever software and firmware make it into a better storage product, but also reduce the usable capacity by 22% compared to a 2TB QLC drive. Since write endurance concerns for consumer storage are usually overblown and the performance benefits are not enough to clearly put the drive into high-end flagship territory, I don't think the FuzeDrive SSD is a good buy. Fortunately, Enmotus has a PCIe Gen4 successor on the way. That should be better able to compete against high-end TLC drives on raw peak throughput, making high-end pricing a more reasonable proposition.
Facebook
Twitter
RSS
45 Comments
View All Comments
powerarmour - Tuesday, May 18, 2021 - link
QLC garbage again, I can hardly contain myself.Samus - Wednesday, May 19, 2021 - link
Understanding QLC's place in the market (cheap bulk flash storage) I'm also struggling to understand who these premium-priced QLC products are for. Seriously who is going to pay 23-25¢/GB for something like this when it's only crutch is high read throughput that has zero real world advantage for virtually all PC users.Wereweeb - Wednesday, May 19, 2021 - link
These products are both proofs of concept, and an advertising for the importance of Caching/Tiering.Enmotus managed to get 3600 TBW out of a 2TB QLC SSD by reducing it's available capacity by a bit and using their software.
philehidiot - Wednesday, May 19, 2021 - link
There is definitely the endurance advantage, but you don't need a commercial product for proof of concept. Indeed, I'd say releasing a commercial product just to prove it can be done where there is no real use for it is a bit daft. Unless they plan to inflict it upon customers in a data collection exercise, using their muscle to force it into laptops. We have already seen the advantages of this kind of tech when smaller SSDs were placed as a cache / tier into HDDs.If their plan is to build this into an industrial product, their proof of concept should be a bunch of engineering samples tested for endurance, not a bodged consumer grade product which seems as though it's going to do more to show you can have a very complex and bodged product and it just about compete with what's already established on the market.
As for advertising, I'd say this is a pretty poor advert. Someone mentioned that Intel's storage division has been held back and it strikes me this is the case. This isn't a new and exciting product, it's two technologies being put together with an inadequate hardware interface and terrible software.
It has potential, but the people who will accept QLC NAND won't know or care what this is and the people who might benefit from the high DWPD won't touch it with a barge pole.
This should have stayed in R&D until it could add something to the market.
Samus - Thursday, May 20, 2021 - link
I'll believe it when it's independently tested. No level of software trickery will enable massive gains in TBW. If you fully write to a drive, the physical cells are fully utilized. Sure you can mask this with a large spare area and aggressive wear leveling but even a 2TB QLD SSD with 4TB of physical NAND (so 2TB spare area) will only yield 4x the endurance and that's best case scenario.Enmotus can't break the laws of physics with intelligent software unless they've come up with some revolutionary hardware deduplication\compression algorithm that is limiting physical changes to NAND by many orders of magnitude, while also eliminating write amplification that is essential to modern ECC for data integrity.
Billy Tallis - Thursday, May 20, 2021 - link
The key advantage the Enmotus drive has over regular QLC drives is that the static SLC portion can be used for far more P/E cycles. On a regular QLC drive, which blocks are used for the dynamic SLC cache is constantly changing, and the fact that a block that's currently operating as SLC may soon be repurposed as QLC effectively prevents it from being rated for more P/E cycles than QLC usage can permit. But with a large pool of permanent SLC, the drive can safely re-use those cells long past the point where they would be unusable as QLC. 128GiB at 30k P/E cycles can on its own handle more total writes than the drive as a whole is rated for.As long as the tiering software does a good job of preventing most writes and write amplification from ever getting to the QLC part of the drive, the endurance rating is completely realistic. The tiering software won't be able to keep the wear confined to the SLC if you are using the drive as a giant circular buffer for video recording or something else that keeps the drive full and constantly modifies all of the data. But most real consumer workloads have a small amount of hot data that's frequently changing and a large amount of cold data that doesn't get rewritten often enough to pose a problem for QLC.
Spunjji - Wednesday, May 19, 2021 - link
Agreed - this would really need to show a serious performance benefit at a similar cost to a TLC drive, or lower cost and similar performance. As it is, it does neither. I'm sure OEMs will lap it up at whatever knockdown price Intel offers it to them to clear the shelves.Spunjji - Wednesday, May 19, 2021 - link
Derped there and confused the price of the Enmotus with the H20... the Enmotus product really does seem to be in a bad place for price vs. consumer appeal without the benefit of Intel's cosy relationship with OEMs.Morawka - Friday, May 21, 2021 - link
The Enmotus product is perfect for Chia miners. Plotting on Chia absolutely destroys consumer-grade SSD's. A 980 Pro will get smoked in around 3 months, whereas this Enmotus drive, even though it's pricier, will last 3-5x longer.Billy Tallis - Friday, May 21, 2021 - link
I think Chia plotting requires more space than the SLC portion of the Enmotus drive, and plotting is an example of the kinds of workloads that would not be handled well by the Enmotus tiering software unless the plotting could fit entirely in the SLC tier.