Mixed IO Performance

For details on our mixed IO tests, please see the overview of our 2021 Consumer SSD Benchmark Suite.

Mixed IO Performance
Mixed Random IO Throughput Power Efficiency
Mixed Sequential IO Throughput Power Efficiency

The Sabrent Rocket Q4 and Corsair MP600 CORE deliver excellent performance on the mixed sequential IO test, leading to above-average power efficiency as well. Their performance on the mixed random IO test is not great, and is actually slower overall than what we saw with Phison E12 QLC drives like the original Rocket Q and the MP400.

Mixed Random IO
Mixed Sequential IO

The earlier E12+QLC drives outperform these new E16+QLC drives across almost all phases of the mixed random IO test, despite using same Micron 96L QLC NAND. On the other hand, the newer QLC drives turn in surprisingly fast and steady results throughout the mixed sequential IO test, though the 2TB MP600 CORE does get off to a bit of a slow start.

 

Power Management Features

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.

For many NVMe SSDs, the closely related matter of thermal management can also be important. M.2 SSDs can concentrate a lot of power in a very small space. They may also be used in locations with high ambient temperatures and poor cooling, such as tucked under a GPU on a desktop motherboard, or in a poorly-ventilated notebook.

Sabrent Rocket Q4 4TB
NVMe Power and Thermal Management Features
Controller Phison E16
Firmware RKT40Q.2 (EGFM52.3)
NVMe
Version
Feature Status
1.0 Number of operational (active) power states 3
1.1 Number of non-operational (idle) power states 2
Autonomous Power State Transition (APST) Supported
1.2 Warning Temperature 75 °C
Critical Temperature 80 °C
1.3 Host Controlled Thermal Management Supported
 Non-Operational Power State Permissive Mode Supported

Our samples of the Sabrent Rocket Q4 and Corsair MP600 CORE use the same firmware from Phison (though Sabrent has re-branded the version numbering). As a result, they support the same full range of power management features. The 4TB Rocket Q4 reports higher maximum power draws for its active power states than the 2TB MP600 CORE, but both drives report the same idle behaviors.

The advertised maximum of 10.58 W for the 4TB Rocket Q4 is alarming and definitely supports Sabrent's suggestion that the drive not be used without a heatsink. However, during our testing the drive never went much above 7W for sustained power draw, which is more in line with the maximum power claimed by the 2TB MP600 CORE (which also tended to stay well below its supposed maximum). In practice, these drives can get by just fine without a big heatsink as long as they have some decent airflow, because real-world workloads will almost never push these drives to their maximum power levels for long.

Sabrent Rocket Q4 4TB
NVMe Power States
Controller Phison E16
Firmware RKT40Q.2 (EGFM52.3)
Power
State
Maximum
Power
Active/Idle Entry
Latency
Exit
Latency
PS 0 10.58 W Active - -
PS 1 7.14 W Active - -
PS 2 5.43 W Active - -
PS 3 49 mW Idle 2 ms 2 ms
PS 4 1.8 mW Idle 25 ms 25 ms

Note that the above tables reflect only the information provided by the drive to the OS. The power and latency numbers are often very conservative estimates, but they are what the OS uses to determine which idle states to use and how long to wait before dropping to a deeper idle state.

Idle Power Measurement

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, and depending on which NVMe driver is in use. Additionally, there are multiple degrees of PCIe link power savings possible through Active State Power Management (APSM).

We report three 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. Our Desktop Idle number represents what can usually be expected from a desktop system that is configured to enable SATA link power management, PCIe ASPM and NVMe APST, but where the lowest PCIe L1.2 link power states are not available. The Laptop Idle number represents the maximum power savings possible with all the NVMe and PCIe power management features in use—usually the default for a battery-powered system but rarely achievable on a desktop even after changing BIOS and OS settings. Since we don't have a way to enable SATA DevSleep on any of our testbeds, SATA drives are omitted from the Laptop Idle charts.

Idle Power Consumption - No PMIdle Power Consumption - DesktopIdle Power Consumption - Laptop

Both the Sabrent Rocket Q4 and Corsair MP600 CORE show quite high active idle power draw, a consequence of their use of a PCIe Gen4 controller made on 28nm rather than something newer like 12nm. However, there's no problem with the low-power idle states except for Phison's usual sluggish wake-up from the deepest sleep. This seems to be worse for higher capacity drives, with the 4TB Rocket Q4 taking about an eighth of a second to wake up.

Idle Wake-Up Latency

Advanced Synthetic Tests: Block Sizes and Cache Size Effects Is QLC Fine for Primetime?
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  • cyrusfox - Friday, April 9, 2021 - link

    Great write up, unfortunate endurance regression (Went from 260 down to 225 cycles), seems only Intel is pushing QLC higher on endurance (200 to 300 to 370 cycles). Impressive random performance though, odd that only Intel appears to be extracting higher endurance with each new gen of QLC though.
  • Samus - Sunday, April 11, 2021 - link

    I noticed that in the 670p review and I'm glad someone pointed it out. I'd like to know if it's a programming\firmware logic thing that extracts better endurance through creative block wear leveling, reduced write amplification (perhaps delayed garbage collection and stuff) or they have more spare area? It's hard to believe they have superior manufacturing compared to "everyone" but maybe they do...
  • Oxford Guy - Sunday, April 11, 2021 - link

    Creativity isn't going to change the fact that there are twice as many voltage states in QLC vs. TLC.
  • cyrusfox - Sunday, April 11, 2021 - link

    With PLC on the horizon, QLC is going to look incredible by comparison :)
    I wonder what the internal goal is to make PLC viable, 70Cycles, 100 cycles? @ 32 Threshold charge states will be an engineering feat all on its own, Impressive QLC is able to function to nearly 400 cycles with 16 separate states(How much are they overprovisioned?).
    From what I see in drive warranties based on underlying nand cells, we see around a 1/4 reduction in endurance/cycles each time they increase the bits per cell (10k,2k,400-1.2K,100-375,20-100). QLC is about 4 years old now with mass market release 3 years ago. PLC is definitely on the near horizon.
  • James5mith - Friday, April 9, 2021 - link

    For the minimal price increase, get the E18 based Sabrent Rocket 4 Plus 4TB model. https://www.amazon.com/dp/B08VF99PV8/
  • HideOut - Friday, April 9, 2021 - link

    Thats still a big price increase. More than $150 even on sale.
  • TheinsanegamerN - Saturday, April 10, 2021 - link

    With far better long term write endurance, write speed, ece. QLC has a nasty habit of slowing WAY down once filled up.
  • Oxford Guy - Sunday, April 11, 2021 - link

    It shows its true performance.

    Once the 'SLC' disguise is gone...
  • wr3zzz - Friday, April 9, 2021 - link

    I don't know why SN550 was used in the performance benchmarks when these QLC drives are priced at premium to SN750.
  • sjkpublic@gmail.com - Friday, April 9, 2021 - link

    For QLC write endurance I look at 600 x size. The numbers here are rather poor. Maybe its a mistake?

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