Mixed Random Performance

Our test of mixed random reads and writes covers mixes varying from pure reads to pure writes at 10% increments. Each mix is tested for up to 1 minute or 32GB of data transferred. The test is conducted with a queue depth of 4, and is limited to a 64GB span of the drive. In between each mix, the drive is given idle time of up to one minute so that the overall duty cycle is 50%.

Mixed 4kB Random Read/Write

This mixed random IO test covers a fairly wide span of the drive, so it's not a surprise to see that the Toshiba/Kioxia BG4 and other DRAMless SSDs end up being among the slowest drives overall, with HMB providing little or no help.

Sustained 4kB Mixed Random Read/Write (Power Efficiency)
Power Efficiency in MB/s/W Average Power in W

The power consumption of the BG4 during this test is as low as any other drive, but the limited performance means its efficiency score is still clearly worse than most of the drives that have their own DRAM.

The performance of the BG4 is low and relatively flat across this test, declining slightly as the workload gets more write-heavy when most drives gain performance. With a working set small enough for the BG4's HMB configuration to be useful, we would likely see a very different performance profile.

Mixed Sequential Performance

Our test of mixed sequential reads and writes differs from the mixed random I/O test by performing 128kB sequential accesses rather than 4kB accesses at random locations, and the sequential test is conducted at queue depth 1. The range of mixes tested is the same, and the timing and limits on data transfers are also the same as above.

Mixed 128kB Sequential Read/Write

The BG4 is a bit more competitive on the mixed sequential IO test, almost matching the XG6's overall performance and more or less tied for fastest among the entry-level NVMe drives.

Sustained 128kB Mixed Sequential Read/Write (Power Efficiency)
Power Efficiency in MB/s/W Average Power in W

The BG4 comes out on top of the power efficiency rankings, with the WD Black SN750 a close second. Even with the lower performance of running without HMB, the BG4 stays near the top of the efficiency chart.

Without HMB, the BG4's performance across the mixed sequential IO test is mostly flat, with a bit of an overall decline as the workload becomes more write-heavy. Enabling HMB allows the BG4 to pick up some speed during the last third of the test, but it doesn't have a huge impact.

Sequential Performance Power Management
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  • cschlise - Thursday, October 31, 2019 - link

    Bought a Dell Inspiron 15 with an AMD processor recently. Dell claimed the laptop was "fixed form factor, but after removing some screws and gently prying the thing open, a wealth of upgrade options were presented. This system had one of the 2230's installed ... sized at 256GB. The board had space for a full 2280 as well as another 2.5mm drive. I installed a 512GB 2280 NVMe and 1GB 2.5mm SSD, and doubled the RAM ... for a fraction of the price Dell would have sold it to me in more expensive configurations.

    Bottom line ... if manufacturers are putting 2230's in consumer laptops, they aren't doing the consumer any favors ... also, if you're buying a "fixed form factor" laptop to save a few $$$, with some careful and steady hands, you'll likely find you can upgrade the sucker significantly.

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