Burst IO Performance

Our burst IO tests run at a queue depth of one and the amount of data transferred is limited to ensure that SLC write buffers don't fill up and controllers don't overheat. In between each burst there's enough idle time to keep the drive averaging a 20% duty cycle, allowing for some buffered writes and deferred garbage collection to be completed. The random read and write tests use 4kB operations and the sequential tests use 128kB operations. All the burst tests are confined to a 16GB portion of the drive, so DRAMless SSDs are not disadvantaged as much as they are for larger tests.

QD1 Burst IO Performance
Random Read Random Write
Sequential Read Sequential Write

The aggressive SLC caching strategy used by the Corsair MP400 and most other QLC NVMe SSDs allows them to provide best-case random IO performance that is competitive with many high-end PCIe 3.0 drives. However, despite the 8-channel controller, the burst sequential IO performance of the Corsiar MP400 is still fairly low by NVMe standards. The Sabrent Rocket Q 8TB's results indicate that at least some of the higher-capacity MP400 models should also be able to provide better burst sequential write speeds by virtue of having larger and faster SLC caches.

Sustained IO Performance

Our sustained IO tests measure performance on queue depths up to 32, but the scores reported here are only the averages for the low queue depths (1,2,4) that are most representative of real-world consumer workloads. Each queue depth is tested for up to one minute or 32GB, and the tests are confined to a 64GB span of the drive.

Sustained IO Performance
Random Read Random Write
Sequential Read Sequential Write

On the longer synthetic IO tests, the Corsair MP400's best results are for random writes, where its SLC cache is sufficient to keep it competitive against high-end PCIe 3 drives. The sequential write and random read performance scores are both constrained to the entry-level NVMe performance ranges, but are competitive for that market segment. The sequential read performance is relatively poor even for entry-level NVMe drives, though still significantly better than Samsung's QLC SATA alternative.

Sustained IO Performance
Random Read Random Write
Sequential Read Sequential Write

With QLC NAND and an aging 8-channel controller, it's no surprise that the Corsair MP400's power efficiency scores are generally unimpressive, especially compared to what the 4-channel NVMe drives score when they are performing well. However, the only particularly poor efficiency score from the MP400 is for the sequential read test that it did not perform well on.

Performance at a glance
Random Read Random Write
Sequential Read Sequential Write

Plotting power and performance against our entire library of benchmark results shows that—for better or for worse—the Corsair MP400 doesn't stand out from the crowd or break new ground. The random read performance stays entirely within the range of SATA drives. Random and sequential writes make some use of PCIe performance, but don't come close to saturating the PCIe 3 x4 interface. The sequential read performance does almost make it to 3GB/s at higher queue depths, but it isn't able to fully saturate the PCIe interface the way the 8TB Sabrent Rocket Q can.

Random Read
Random Write
Sequential Read
Sequential Write

Digging into how performance and power scale with increasing queue depths reveals no particular surprises for the Corsair MP400. The biggest discrepancies with the 8TB Sabrent Rocket Q are for random reads and sequential writes: more flash allows the 8TB drive to continue scaling up random read performance after the 1TB MP400 is starting to reach saturation, and the larger SLC cache for the 8TB drive allows higher and more consistent sequential write performance.

AnandTech Storage Bench Mixed Read/Write Performance And Power Management
Comments Locked

75 Comments

View All Comments

  • Spunjji - Monday, December 14, 2020 - link

    This is the only one of the anti-QLC tropes I see routinely rolling around this comment section that I 100% unequivocally agree with.

    A quick scan through a certain UK retailer shows the cheapest 1TB drive is the Intel 665p at £89, with the cheapest (relatively crappy) TLC drive at £96 and a WD Blue at £103. Worse still, at the 2TB level the positions flip and the WD Blue is *cheaper*.

    At the 1TB level, even though I know objectively that the 665p would be fine for my purposes I'd still be tempted to pay the £14 extra for the Blue. If the difference were £25 or more, I wouldn't.
  • GeoffreyA - Monday, December 14, 2020 - link

    It's as if margarine were suddenly the same price as butter, or quite close, and the makers, exterting their marketing force, succeeded (almost succeeded) in blurring the distinction between the two.

    It would be nice if somebody did a giant endurance experiment, finding out exactly where these QLC drives stand, like the one Techreport tackled in 2015, writing an horrific number of TBs till the drives "breathed their last." There will be surprises.
  • Oxford Guy - Monday, December 14, 2020 - link

    They will succeed. Getting everyone to go to a small form factor was very helpful, along with, apparently, not producing TLC in 1024Gbit dies.

    Margarine was superior to butter back in the day, remember? Superior partially hydrogenated technology. Because they said so.
  • Oxford Guy - Monday, December 14, 2020 - link

    Not the best comparison, though – since butter was still widely available for reasonable prices.

    QLC, by contrast, is intended to ruin the economy of scale of TLC. We could find farmers with butter churns pretty easily. Not so easy to find small-scale TLC foundries for the peasantry.
  • GeoffreyA - Tuesday, December 15, 2020 - link

    "Margarine was superior to butter back in the day, remember? Superior partially hydrogenated technology. Because they said so."

    Nice one.
  • Oxford Guy - Monday, December 14, 2020 - link

    QLC doesn't need "tropes" any more than it needs cheerleading.

    Reality is that 16 voltage states is more problematic than 8 and fewer.
  • boredsysadmin - Monday, December 14, 2020 - link

    I 100% agree with @kpb321
    I am also surprised that SK Hynix Gold P31 didn't make the last page budget consumer NVMe SSDs. MP400 1TB costs $114 on amazon, while one of the fastest budget drives in the review, P31 1TB, is currently at $120.60 - Which one you'd buy? I am "puzzled" by QLC drive makers' greed to raise the price per TB on bigger drives. They aren't the first to fill that niche - I expect the opposite - higher drives to be more expensive but priced the same or cheaper per TB.
  • Drkrieger01 - Friday, December 11, 2020 - link

    I love how everyone's up in arms at 'Endurance'. Let me give you some insight on just how much 'endurance' you really need. I build a 'high speed storage' server, 16x 840 Evo 1TB, LSI MegaRaid 9750 16i back in 2014. We've been pounding the piss out of this server for *6* years. Not a single drive has reallocated sectors. I believe we've crossed a few petabytes on some of the drives, even after having to flash firmware updates and re-zero the drives due to the decay issue on the 840 Evo's.
    I'm sure these new drives will be just fine for the average user.
  • inighthawki - Friday, December 11, 2020 - link

    Let's not forget that most people aren't coming *remotely* close to what you're doing. I bet even most power users would struggle to *consistently* write more than 10-20GB per day average to these drives. Hitting the endurance ratings at these rates would take decades. The SSDs will have been long discarded by that point.

    Even for the exceptional power user writing 100+GB a day, they would need to consistently do that every day for nearly 6 years to hit the endurance cap on the 1TB model. A user like this will also likely replace these drives within that time frame.
  • Tomatotech - Friday, December 11, 2020 - link

    I have little to no worry about endurance for the vast majority of users even with QLC, and even that problem will go away with 2TB+ QLC.

    That said, your use is unusual, and the 840s were particularly good drives especially with 1TB. The same usage patterns with 256gb TLC or 512GB QLC might well have seen them wear out. Thankfully we’re past that stage now. However you still had to flash firmware and re-zero the drives, and most people with SSDs nowadays won’t know how to do that.

Log in

Don't have an account? Sign up now