The Intel Optane SSD 900P 280GB Review
by Billy Tallis on October 27, 2017 9:30 AM ESTDrive Features
Intel's strategy for developing the Optane SSD 900P is the same they used for the SSD 750 in 2015. Both products are consumer-oriented derivatives of the flagship enterprise SSD of their time. As with the SSD 750, this has resulted in the Optane SSD 900P being a physically large and power-hungry drive that can't come close to fitting in the M.2 form factor used by most other consumer PCIe SSDs. The controller alone on the Optane SSD 900P is too large to fit on a 22mm-wide M.2 module, and its idle power draw of 5W is more than most M.2 PCIe SSDs draw under load.
The Optane SSD 900P shares the same platform as the enterprise Optane SSD DC P4800X. It uses the same Intel controller with a PCIe 3.0 x4 link to the host system and a seven channel interface to the 3D XPoint memory. The P4800X is available as a 375GB drive that uses four dies per channel for a raw capacity of about 448GB. The 900P uses three or five dies per channel and similar overprovisioning ratios to offer usable capacities of 280GB and 480GB from raw capacities of about 336GB and 560GB. Because 3D XPoint memory supports direct read and in-place write operations with bit granularity instead of being constrained by the page and block structure of NAND flash memory, the Optane SSD 900P isn't using the extra capacity as spare area for any garbage collection process and is likely instead devoting most of it to error correction overhead and metadata.
The odd capacities and channel counts of the Optane SSD 900P aren't a requirement for using 3D XPoint memory so much as they are a consequence of Intel's performance and power targets for the drive. However, the use of 3D XPoint memory does lead to a few striking hardware design differences from flash-based SSDs. The Optane SSD 900P does not have any DRAM cache. On a NAND flash-based SSD, this would be a major red flag indicating reduced performance, even when mitigated by the NVMe Host Memory Buffer feature. Flash-based SSDs need quick access to the mapping tables that track which logical blocks are stored in which physical pages. 3D XPoint memory, on the other hand, is much simpler to manage, with no need for garbage collection and little or no need for wear leveling, and the storage medium itself is far faster. This makes the large DRAM buffer unnecessary.
The lack of buffers seems to also extend to the individual 3D XPoint chips themselves. NAND flash dies include page-sized RAM buffers as intermediate storage between the controller and the flash memory array. This allows the controller to transfer the payload data for a write command to the NAND die and then move on to issuing other commands to other dies on the same memory channel (or other planes on the same die) while the relatively long NAND program operation is happening. This multiplexing of operations within a single memory channel is a large part of why flash SSDs tend to be faster at higher capacities even within the same product line with the same SSD controller. The Optane SSD 900P accesses its 3D XPoint memory more directly and read and write operations are completed synchronously without an intermediate buffering stage. This means that the 280GB and 480GB models have essentially the same performance, and this same level of performance could in theory extend down to a one die per channel configuration that would offer 112GB raw capacity and 96GB usable capacity (and could be profitably sold for under $180).
While the lack of RAM buffers on the Optane SSD doesn't bring any major performance problems, it does have one minor downside. Flash-based SSDs are able to aggressively take advantage of their buffers to accept write operations almost as fast as the PCIe link allows for, so the Optane SSD 900P doesn't have much room to improve peak write speeds beyond what the 3D XPoint memory itself can sustain. However, the Optane SSD can continue providing those write speeds long after a flash-based SSD would have stalled to let the flash catch up to the controller.
The last major implication of the DRAMless design of the Optane SSD 900P is that large banks of capacitors are unnecessary to provide power loss protection. The Intel SSD 750 was one of the few consumer SSDs to offer enterprise-grade power loss protection, but those capacitors added to an already high BOM and were probably only kept to save the effort of more significant firmware changes relative to the enterprise SSDs it was based on. With the Optane SSD 900P, Intel gets to retain power loss protection on the consumer version more or less for free. This allows the Optane SSD 900P to avoid the consequences of Microsoft's stupid NVMe driver write cache policy defaults, which severely curtail the write performance of consumer NVMe drives that have volatile write caches. (Our client SSD test protocol uses the more reasonable but non-default write buffer policy for all Windows-based tests, so this advantage doesn't show up in out performance charts.)
When an SSD vendor makes consumer and enterprise drives based on the same controller platform, there are usually major firmware differences to optimize for different performance requirements. Consumer SSDs tend to use SLC write caching to offer better burst write performance while enterprise SSDs tend to avoid it to offer more consistent performance. There are few opportunities with the Optane SSD to tweak performance between the consumer and enterprise versions, but there are several features from the P4800X that have been omitted from the 900P. The only one that has any performance impact is the ability to reformat the P4800X to use a 4kB logical block size instead of 512 bytes; the 900P only supports 512B sectors and doesn't support end-to-end data protection. The 900P also omits the SMBus interface for out of band management and doesn't include the diagnostic LEDs.
The most significant functional difference between the P4800X and the 900P is the endurance rating, which has been reduced from 30 drive writes per day to 10 DWPD. That's still a very high figure for a consumer SSD, but Intel's policy of putting the drive into read-only mode when the rated endurance is reached can be a nuisance, and it'll be encountered sooner on the 900P. The difference in write endurance is proportional to the price difference between the 900P and the P4800X, so the de-rating isn't too unfair. Overall, the Optane SSD 900P is still the closest a consumer SSD gets to offering enterprise SSD performance and features, and the 900P will probably cannibalize some P4800X sales.
Note that our usual set of power measurements is unavailable due to an equipment failure. The Optane SSD 900P will be re-tested once we have a new power meter, and the results will be posted to the SSD Bench database. In the meantime, rest assured that the Optane SSD 900P won't win any awards for efficiency.
| AnandTech 2017 SSD Testbed | |
| CPU | Intel Xeon E3 1240 v5 |
| Motherboard | ASRock Fatal1ty E3V5 Performance Gaming/OC |
| Chipset | Intel C232 |
| Memory | 4x 8GB G.SKILL Ripjaws DDR4-2400 CL15 |
| Graphics | AMD Radeon HD 5450, 1920x1200@60Hz |
| Software | Windows 10 x64, version 1703 |
| Linux kernel version 4.12, fio version 2.21 | |
- Thanks to Intel for the Xeon E3 1240 v5 CPU
- Thanks to ASRock for the E3V5 Performance Gaming/OC
- Thanks to G.SKILL for the Ripjaws DDR4-2400 RAM
- Thanks to Corsair for the RM750 power supply, Carbide 200R case, and Hydro H60 CPU cooler
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phaethon1 - Tuesday, November 14, 2017 - link
Nice post,I read in multiple channels about this SSD being able to be used as extra RAM. Then I contacted the technical support of Intel, and they do not have any clue about a software to enable this feature. Any ideas?
extide - Friday, October 27, 2017 - link
SLC might be faster in sequential, but if you want sequential stripe a bunch of platters ..Also, I didn't say bit-level, I said block level. They present 512b blocks so you would assume the drive manages 'pages' in the size of 512b even though the underlying memory can be more fine-grained. SLC can't do that, plus there is still the whole garbage collection thing. If your hypothetical drive was actually a good idea, someone would make it. That's proof enough that it's not.
ddriver - Friday, October 27, 2017 - link
They didn't make one not because it is not good enough, but because it would be too good.That would set a bad precedent. Before you know it, people will start demanding quality rather than being content with what the industry dictates to them.
Of course, if hypetane manages to make enough a hole in the pockets of big players, we will definitely be seeing some of that long-possible, deliberately untapped potential coming to life.
"That's proof enough that it's not."
You know, they make trucks that drive 24/7, under huge loads, and can go much long without maintenance than a regular personal vehicle. That's proof enough that the industry doesn't make things as good as it can, obviously, if it can make a heavily used and loaded truck more durable, that would be not only possible, but actually much easier to achieve for a regular car that's driven less, under less load. Yet they don't make it, even if that ends up costing human lives. And the reason for that is moar profit. Which is why they chose to only overbuild trucks, because that too maximizes profits. But not cars. Cars are far more profitable if need more servicing, and that doesn't result in profit losses as it would if it was commercial trucks, and if underbuilt cars end up costing human lives, that's a small price to pay for more profit. Engineering wise, is entirely possible and easily doable to make a car about 10 times more durable, and requiring 10 times less maintenance, and 10 times safer too, but they'd rather get the extra profit. And keep good engineering exclusive to military and commercial production.
The reason they haven't made it is they didn't have a reason to make it. And the reason intel did hypetane is only because it has been a very long time since they did anything new. They had that in the works, and decided to release it in order to demonstrate some innovation, unfortunately, not without shamelessly lying about how well it will perform in advance.
Xpl1c1t - Friday, October 27, 2017 - link
ddriver, i like your analysis. maybe the review system just wasnt equipped with rgb lighting, that would explain at least one order of magnitude of error in their results vs Intel's promisesjospoortvliet - Friday, November 3, 2017 - link
> Engineering wise, is entirely possible and easily doable to make a car about 10 times more durable, and requiring 10 times less maintenance, and 10 times safer too, but they'd rather get the extra profit. And keep good engineering exclusive to military and commercial production.Well, yes, they care about their profits: nobody would buy such a super-durable car because it would cost 5-10x the price and people will go for the cheaper car, even though it has higher maintenance cost. This is true for nearly ANY product on the market: sure, you could built houses more durable, or bikes, or... you name it. But people prefer 'good enough' over 'perfect', always have. And they're not entirely stupid - many products' practical life time is fine, people quite like buying a new car every 3-5 years. Or new cups. Or new forks and knives.
Yes, some folks pay the 10x price to get the perfect, durable stuff. But most buy pressed wood closets at Ikea and are happy with it.
Gastec - Saturday, March 10, 2018 - link
I'm not sure if you are both ironic or are just too rich to think straight.AlishaScott - Sunday, October 29, 2017 - link
I just got paid $6784 working off my laptop this month. And if you think that’s cool, my divorced friend has twin toddlers and made over $9k her first month. It feels so good making so much money when other people have to work for so much less. This is what I do... http://cutt.us/O5gexNails6365 - Monday, November 6, 2017 - link
Thank you for your in-depth analysis.Given the opportunity to make a high-end rig. What would you choose ?
Jared13000 - Tuesday, May 22, 2018 - link
You’re not giving Optane enough credit, you don't necessarily compare a NAND based drive to an Optane based drive. Compare NAND to Optane, as NAND has had years of development pored into hiding its short comings that Optane has not yet had.I just built a small all flash hyper converged cluster and after setup I was getting about 500,000 random read IOPS on a quad node cluster with triple mirrored storage. Write speeds were about 1,000 IOPS, basically hard drive speeds across the 16 SSDs in the cluster.
Was it bad drivers, miss configuration, ethernet flow control issues?
None of the above. It was the drive cache. Storage spaces disabled it due to the drives not having power loss protection. Enabled the cache on all the drives to avoid direct NAND writes and now the cluster can push nearly 280,000 write IOPS. This mean with cache the drives are over 200 times faster than just writing directly to NAND.
What does this have to do with Optane? As far as I have been able to find, Optane drives don't have or need a cache. Their performance is direct to storage, without cache!
Taken in the context of NAND vs Optane, 1,000x may be embellished, but probably not by much. At this point PCIe overhead and lack of software optimization may be the only reason it’s not 1,000x faster when comparing modern NAND memory.
It's not that much faster comparing a whole NAND drive with well implemented cache to an Optane drive, but some situations can't rely on cache. Also, a simpler drive should be more reliable, in theory.
As it is Optane is unrivaled until someone manages to bring a drive to market with SLC NAND and nonvolatile cache like MRAM for about twice the cost of a 970 PRO.
Just a thought, a 970 PRO 512 GB has an MSRP of $329 and the Intel 900p 280 GB has it’s MSRP at $329 as well. That is 256 GB of SLC flash vs 280 GB of Optane. Comparing an MLC drive to an SLC drive at half the capacity is a bit like comparing apples and oranges, but it’s a start for an estimate. Trade the DRAM for MRAM and bump the capacity a bit and it’s hard to imagine that a SLC NAND based drive with MRAM wouldn’t cost more than Optane.
If you expected 1,000 times SSDs that are getting multiple gigabytes per second reads and writes, then you were looking for a drive faster than CPU cache. Intel really needs to watch their wording, but that does not make this a bad product.
CheapSushi - Friday, October 27, 2017 - link
Well, then wait for Samsung's Z-NAND, which is MLC/TLC NAND treated like SLC.