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

  • madmilk - Saturday, December 12, 2020 - link

    The 840 Evo is probably the worst drive Samsung has ever shipped. The first gen 2D TLC memory in the drives caused a ton of performance issues thanks to losing the charge in the flash cells leaking out rather quickly. Samsung had to push out a bunch of firmware bandaids for the issue and switched to 3D TLC for the 850 Evo. Even then, I don't think many people managed to wear them out.
  • Beaver M. - Saturday, December 12, 2020 - link

    My 840 is stored at low temperatures 5 months a year without any power source. Still works like new.
  • Spunjji - Monday, December 14, 2020 - link

    The 840 (not Pro, not Evo) would definitely take that title - it's like the Evo but without any caching or a firmware fix for the read degradation. Even with that said, I still have a couple of the absolute worst-case drives - the 840 120GB - hanging around in service as boot drives for seldom-used systems, which is a role they perform relatively well even in spite of their unique form of bit-rot. Maybe it's because Windows 10 basically rewrites the whole damn OS every 6 months? 😂
  • Oxford Guy - Monday, December 14, 2020 - link

    "which is a role they perform relatively well even in"

    Not according to HardOCP which found they had worse steady state performance than laptop hard drives.
  • Gigaplex - Wednesday, December 16, 2020 - link

    It was still better than the 840 non-Evo
  • Beaver M. - Saturday, December 12, 2020 - link

    If your case is worth anything, then the logical conclusion for SSD manufacturers should be to increase warranty and TBW massively.
    Huh. I wonder why they dont.
  • joesiv - Monday, December 14, 2020 - link

    Care to share your SMART data for one of the drives? I'm curious.
  • lmcd - Friday, December 11, 2020 - link

    While this drive is an interesting reference point, that extra $20 (or less) for a SK Hynix P31 is easily worth it.
  • Zzzoom - Friday, December 11, 2020 - link

    DWPD calculations on page 1 are wrong.
  • zepi - Saturday, December 12, 2020 - link

    This latest gen QLC with 8 channels looks too good so that it would disappear...

    In sizes from 2TB and up, it iss probably a good choice for anyone looking for a cheap drive. And thanks to SLC caching 4k random writes are crazy fast.

    One can always increase SLC cache amount by leaving 50-100G unpartitioned to make sure there is good amount of SOC cache even when filling the drive with one more Steam download.

Log in

Don't have an account? Sign up now