Power Management

Real-world client storage workloads leave SSDs idle most of the time, so the active power measurements presented earlier in this review only account for a small part of what determines a drive's suitability for battery-powered use. Especially under light use, the power efficiency of a SSD is determined mostly be how well it can save power when idle.

SATA SSDs are tested with SATA link power management disabled to measure their active idle power draw, and with it enabled for the deeper idle power consumption score and the idle wake-up latency test. Our testbed, like any ordinary desktop system, cannot trigger the deepest DevSleep idle state.

Idle power management for NVMe SSDs is far more complicated than for SATA SSDs. NVMe SSDs can support several different idle power states, and through the Autonomous Power State Transition (APST) feature the operating system can set a drive's policy for when to drop down to a lower power state. There is typically a tradeoff in that lower-power states take longer to enter and wake up from, so the choice about what power states to use may differ for desktop and notebooks.

We report two idle power measurements. Active idle is representative of a typical desktop, where none of the advanced PCIe link or NVMe power saving features are enabled and the drive is immediately ready to process new commands. The idle power consumption metric is measured with PCIe Active State Power Management L1.2 state enabled and NVMe APST enabled (when supported).

Active Idle Power Consumption (No LPM)Idle Power Consumption

(idle power)

Idle Wake-Up Latency

(idle wake-up)

Mixed Read/Write Performance Conclusion
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  • eddman - Sunday, December 17, 2017 - link

    That graph explains the situation perfectly. Even if the media's latency was somehow magically reduced to zero, the total storage latency would still be only about 6 times better.

    It's all pointless though; ddriver's personal hatred towards intel and "the corporations" prevents him from thinking differently. As soon as he finds a number that is different from what was mentioned in the promotional materials, the first thing he does is to start shouting "liar, liar".

    P.S. I have zero love for corporations and can't stand when one takes advantage of the users. What I also can't stand is a person spreading unsubstantiated claims and spamming a technology website's comment section to offload his hate in order to feel better.
  • tuxRoller - Friday, December 15, 2017 - link

    Also z nand appears to be mlc cells operating in SLC mode, and that's still slower than first gen xpoint.
  • hescominsoon - Friday, December 15, 2017 - link

    Intel has walked back the 100x bs claims. Also notice how micro(their partner in this venture) has NOT released their side of this product?
    https://semiaccurate.com/?s=optane
  • tuxRoller - Saturday, December 16, 2017 - link

    They walked them back? Maybe for these nvme products, though I've not seen anything about that. The real test is how well they'll do as direct addressed memory when used in the DIMM configuration.
  • Reflex - Friday, December 15, 2017 - link

    SLC has no significant advantages over Optane. Optane is nearly across the board a better performer, often by a significant margin, than any commercial NAND technology. The two drawbacks that are important right now are power consumption and cost (these are also drawbacks of SLC for the record)

    The complaints about Intel's 'hype' are misconstrued. There is a huge difference between discussing what a technology is capable of, and what individual products derived from that technology can deliver. That some people had reading comprehension problems is not Intel's problem, they are delivering what they promised, and as the rest of the supporting infrastructure improves over time we know based on their initial statements that Optane/PCM can scale to match it.
  • CheapSushi - Friday, December 15, 2017 - link

    The industry is trying. It's called Z-NAND.
  • ddriver - Friday, December 15, 2017 - link

    Which is MLC...

    Samsung realized nobody is catching up in the nand market and decided to push consumer, high end and mainstream enterprise a notch down to TLC.

    So now that MLC is only a "high end enterprise" thing in their portfolio, they decided to pimp it up with a new moniker - z-nand. Alas, it is just good old MLC with a barely incremental controller. And claim that it has anything to do with SLC performance - which it does as much as an a race horse harness makes an old donkey faster.

    They REALLY aren't trying.
  • CheapSushi - Saturday, December 16, 2017 - link

    It's MLC & TLC 3D NAND treated exactly like SLC (1 bit per cell) with a better controller and special sauce, effectively making it as if it was SLC in the first place and a better SLC driver than previous SLC drives that came out. So what is the issue? It's not a completely separate NAND production line?
  • ddriver - Saturday, December 16, 2017 - link

    Do you realize parroting nonsense you are clearly completely ignorant of doesn't win you bonus points?

    There is no such thing, you have to compromise one for the sake of the other. It is just more mature and a tiny bit better than previous gen MLC, but it is not even half of what can be squeezed of contemporary SLC.

    "Special sauce"? It is sad to see average Joe hans't moved up a bit since the middle ages.
  • drajitshnew - Saturday, December 16, 2017 - link

    No "ryzen" in opposition to their "core". The flash industry is in a race to see who can make the CHEAPEST PoS

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