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.

Active Idle Power Consumption (No LPM)Idle Power Consumption

Idle Wake-Up Latency

The Optane SSD 800p has a bit of an unusual suite of power management capabilities. Previous Optane products have not implemented any low-power sleep states, giving them quite high idle power consumption but entirely avoiding the problem of latency waking up from a sleep state. The 800p implements a single low-power sleep state, while most NVMe SSDs that have multiple power states have at least two or three idle states with progressively lower power consumption in exchange for higher latency to enter or leave the sleep state. On the other hand, the 800p has three tiers of active power levels, so devices with strict power or thermal limits can constrain the 800p when properly configured.

Unfortunately, our usual idle power testing method didn't work with the 800p, leading it to show only a modest reduction in power rather than a reduction of multiple orders of magnitude. This may be related to the fact that the Optane SSD 800p indicates that it may take over a full second to enter its idle state. This is an unusually high entry latency, and something in our system configuration is likely preventing the 800p from fully transitioning to idle. We will continue to investigate this issue. However, based on the specifications alone, it looks like the 800p could benefit from an intermediate idle state that can be accessed more quickly.

(I should mention here that the last Intel consumer SSD we reviewed, the 760p, also initially showed poor power management on our test. We were eventually able to track this down to an artifact of our test procedure, and determined that the 760p's power management was unlikely to malfunction during real-world usage. The 760p now ranks as the NVMe SSD with the lowest idle power we've measured.)

Mixed Read/Write Performance Conclusion
Comments Locked

116 Comments

View All Comments

  • Reflex - Thursday, March 8, 2018 - link

    I'm sorry you know how many are rushing out to buy a product that isn't available yet? I don't personally expect large volumes since at the current capacities it isn't in the sweet spot for consumers in price/perf, but its offering solid performance that bests NAND in almost every consumer scenario, in some cases significantly while consuming less overall power. That's a win. As production ramps, costs will come down.

    And only the literacy challenged have chosen to read Intel's claims about 3DXPoint's potential as claims about its first generation products. Right now its constrained by a number of things beyond the memory itself, such as PCIe bus speed.
  • iter - Friday, March 9, 2018 - link

    And I am sorry don't possess common sense.

    Of course I am not talking about how the 800p sells, only a complete idiot could take this out of my comments. I am talking about the non-existent demand for it in the enterprise, which the introduction of the 800p is another testament to.

    If intel was able to sell it at high enterprise margins they wouldn't be forcing it in the consumer world where it is pointless. Intel is not keep on losing money, and as overpriced as it is even as a consumer product, it is tremendously cheaper than what they can ask for it at the enterprise market. Instead they are marketing it to frigging games... which is 100% laughable.

    And of course, I don't expect anyone save for silly fanboys with rich mommies to buy it in the consumer world. because it can offer absolutely nothing for the price premium it comes at. No intelligent human being would pick a 118 gb 800p to a decent 256 gb nvme or 512 gb ssd drive. None whatsoever.

    Constrained by PCIe? It doesn't even come close to that. Neither in terms of bandwidth nor latency. But believe whatever it takes to reinforce your fake worldview.
  • Luckz - Wednesday, April 25, 2018 - link

    Is there actually a point to 256 gb NVMe though? I mean, performance of the small 960 Evo sucks balls compared to the bigger ones. Why go NVMe when you can have a nice SATA drive with much more capacity and not even much worse perf?
  • Adramtech - Saturday, March 10, 2018 - link

    iter, Lehi fabs are 100% dedicated to Xpoint and no longer NAND. They wouldn't commit billions to that if they didn't have a path outlined for improvement and scaling.
  • patrickjp93 - Saturday, March 10, 2018 - link

    Are you kidding? AWS Memcached, Lambda, and DynamoDB have their caching layers and indexing stored in Optane.
  • eddman - Saturday, March 10, 2018 - link

    We just found ddriver's long lost twin brother.
  • Alexvrb - Saturday, March 10, 2018 - link

    Cloning tech gone wrong.
  • Reflex - Saturday, March 10, 2018 - link

    It's not his twin, it's just his new account. This place had a much better community during the too brief time he was gone.
  • patrickjp93 - Saturday, March 10, 2018 - link

    3DXP is being made on the 90nm node right now. What did you expect? It's a vastly cheaper research node for something so complex.

    And the performance is stunningly better than everything else Samsung has EXCEPT for high Queue Depth sequential performance. All real world testing shows the 960Pro getting smashed.
  • Reflex - Saturday, March 10, 2018 - link

    Didn't you hear the memo that because this first gen product isn't as good as the theoretical max performance discussed three years ago its all a big fail? /sarcasm

Log in

Don't have an account? Sign up now