First Look: Intel’s Optane Memory Cache SSDs
After more than a year of hype and speculation, the first products featuring Intel and Micron’s breakthrough 3D XPoint memory technology (pronounced "cross-point") are about to come to market.
Intel is leading the way with caching drives in 16GB and 32GB capacities under the brand name "Optane." These memory-stick-style drives are designed for use on 7th Generation ("Kaby Lake") PCs, and full-out client solid-state drives (SSDs) based on 3D XPoint to follow sometime in the future. The drives will be available starting on April 24 and will sell for $44 and $77, respectively. All that's needed to run them is a Kaby Lake CPU and an M.2 Type-2280 slot for the Optane drive. The idea is that you would pair the Optane caching drive with a platter-style hard drive; that’s how it’s designed to be used. (You can also install it alongside a GPT-formatted SATA SSD, though the increase in performance will be less noticeable than with an Optane cache drive and a hard drive.)
If you missed all the buzz, "3D XPoint" is the name of the new memory technology, while "Optane" is the branding for the products that use it. It was designed by Intel and Micron as something of a cross between ultrafast DRAM and high-capacity, affordable NAND flash.
The difference between the two memory types is that DRAM is expensive (thus, necessarily lower-capacity) and volatile, meaning it needs power to retain data, whereas NAND is comparatively cheap, can scale to high capacities, and is non-volatile. "Non-volatile" means it holds data without staying under power, which is why it’s used in flash drives and SSDs.
3D XPoint is supposed to deliver the benefits of both technologies, delivering DRAM-like low latency at NAND capacities, with pricing falling somewhere between the two. As for what makes it tick, 3D XPoint is rather cloaked in mystery. Intel isn’t saying what materials it uses for it, but it’s essentially a 3D mesh that does not use transistors, so it’s unlike anything we’ve ever seen before. Draw what you will from the schematic below.
The First Optane Hardware
Though it’s being touted as a "do it all" storage solution of sorts that might one day even come in a DIMM form factor, for now Intel is releasing it one product at a time.
Intel’s first Optane product was announced recently: a 375GB enterprise SSD named the "DC P4800X," priced at $1,520 and meant for data centers. It’s being followed by today’s announcement of the 16GB and 32GB caching drives. Though NAND drives cost about 30 cents per gigabyte, Optane is ringing up at about $2.75 per gig for the memory in the caching drives and $4 per gig for that in the enterprise SSD. This makes it much cheaper than DRAM, but obviously way more expensive than NAND, so pricing is falling around where we expected.
As far as the caching drives go, they are identical to modern PCI Express NVMe SSDs, in that they use an M.2 form factor and ride the PCI Express bus. (See our guide to the best M.2 solid-state drives.) As such, you will need an M.2 Type-2280 slot to install one, but that won’t be an issue as they are only compatible with Intel’s newest "Kaby Lake" CPUs; any late-model motherboard that supports Kaby Lake will likely have an M.2 slot.
The reason for the limitation to Kaby Lake, as was explained by Intel at a recent press event, is because that's the only system platform it has validated for use with Optane. Intel could also have validated it with its previous 6th Generation/"Skylake" environment, but to be fair to Intel, when asked about this, company reps said it would require too many resources to validate hundreds of motherboards and all its previous CPUs. So it went with its newest platform; that’s where its current focus lies.
Optane Speed: The Claims
So, we know pricing for the first Optane consumer silicon; what about performance? This is where we get into a semi-grey area, for a few reasons. First off, when Intel announced 3D XPoint, it claimed it was “1,000 times faster than NAND flash,” and it still does. However, the way Intel is using the word “faster” is different than what you might expect.
That’s because when we think of SSDs that use NAND flash today, we think mostly about sequential-read and -write performance. Optane won’t be breaking any performance records in those categories. But that’s not what it was designed to do. Instead, its main benefit is incredibly low latency, and its ability to maintain performance levels as workloads increase.
Instead of being able to read and write large files quickly, Optane is designed to be much more responsive than NAND, with latency measured as an order of magnitude faster than NAND (nanoseconds, compared to microseconds). Basically, it’s “faster” in the sense that it has much lower latency, and can respond to requests for data much more quickly. It is also more effective at much lower queue depths than NAND. Compared to NAND, however, at least for home users, it is probably not worth the cost in large amounts; thus, we have the caching drives to help out folks who are stuck with a hard drive as the lone storage device in their systems.
Intel claims Optane can “switch states” 1,000 times faster than NAND flash, and it also doesn’t matter what size the drive is or what the load is; it’s pretty consistent at all times, according to slides Intel showed the media. Unlike SSDs that require a high queue depth to reach their maximum performance, the Intel Optane can achieve its maximum performance at a queue depth of just one request, at least when it comes to random reads and writes. And even if you scale it up to 128 requests, performance should barely change.
Higher or lower capacity also doesn’t affect performance in the way it does with NAND-based SSDs. That said, Intel has stated that its Optane memory is capable of 1.2GB-per-second sequential reads, and just 280MB per second for sequential writes. Its random read performance, however, is quite high (the claim is 300K IOPS), with random writes at just 70K IOPS. The rated endurance also looks to be high, with the drive capable of 100GB of writes per day.
According to Intel, since it’s a caching drive, it exists to boost the performance of your most-used applications. One of Intel's launch claims, according to its own testing in SYSmark and PCMark Vantage, is that it can increase overall system performance by as much as 28 percent, and storage performance (versus just a hard drive alone) by 14x. Additionally, Intel says testing has shown speed improvements in game launches by up to 18 percent, and level-loads by up to 58 percent. Those claims, especially the storage performance one, sound optimistic, but we'll see when we get hands on with the technology.
Optane: The Logistics & the Forecast
The way it works? You install the Optane stick in a compatible Kaby Lake board's M.2 slot and run Intel’s Rapid Storage Technology software, and the Optane drive caches the most frequently stored files.
Though we've seen solutions like this before using the same basic concept (witness various caching solutions done some years back via mSATA cards), it’s fair to say none of them have really caught on. They do work, but they’ve never fully delivered on all-out SSD speeds, and the economics have not been in their favor.
Intel hopes to change that with Optane. In a demo prepared for us by Intel at the launch event we attended, we ran a few apps with just a hard drive, then again with the Optane drive installed, and indeed noted it was much faster. We weren't able to record the exact numbers we saw, but a ballpark figure we recall was a photo operation in GIMP taking 20 seconds with a hard drive, and 6 seconds with the Optane drive in play.
The Optane technology seems promising enough, and we should have hardware to test very soon, so stay tuned for proper benchmarks. Our only concern with these initial Optane products—the caching drives—is pricing. If you're building a Kaby Lake PC from the ground up, an Optane cache doesn't seem to make much sense, as you can buy a decently sized boot SSD these days for $75 or so and get a hard drive alongside it, with the two separately addressable. More the idea is that you can add one of these caching drives to a system that has just a hard drive, to boost speeds without replacing the hard drive.
If it turns out that the Optane caches are a lot cheaper for OEMs to buy, it's possible they may appear in upcoming budget-minded desktops, with an Optane cache and a cheap hard drive paired up to provide a cost-efficient but still-snappy storage solution. Intel did note that in the second quarter of 2017, PC makers such as Dell, Lenovo, HP, and Acer will be shipping business and consumer PCs making use of this Optane memory. We'll be interested to see how that shakes out as 2017 advances.
ComputerShopper may earn affiliate commissions from shopping links included on this page. To find out more, read our complete Terms of Service.
Source: http://feeds.computershopper.com/~r/ComputerShopperFeatures/~3/h9j7OnF7gc0/first-look-intel-s-optane-memory-cache-ssds
No comments: