We used CrystalDiskMark 8’s custom settings to test the 4K 70/30 mixed read/write performance of the drive through a range of queue depths using a single thread and four threads.
WD's Black SN850X produces strong performance in our 70/30 read/write test, particularly when using four threads. Using a single thread the performance climbs from 22,524 IOPS at QD1 to 139,702 IOPS at QD32. With four threads the QD1 figure rises to 84,444 IOPS and climbs steadily as the queue depth deepens to finish the test run at 390,390 IOPS at QD32.