We have conducted performance stress tests using an LSI 3108 RAID controller via Thunderbolt 3, configured with 4 HDDs in RAID 5. The results from AJA System Test Lite (4GB, 10-bit RGB) and fio (BS=1M, iodepth=32, Direct=1) show that I/O throughput in Bundled Mode remains at approximately 800 MB/s, which is identical to the performance measured in Legacy Mode. Do either of these tests generate parallel I/O (meaning, multiple threads are generating I/O to the same target)? More specifically, I'd look at: Parallel I/O within the test itself. I/O targeting different partitions on the same target. I/O targeting unrelated targets on the same controller. Also, what does your overall I/O flow look like? Is your card receiving commands fast enough that it's processing them in parallel, even though they arrived as separate commands? What's your peak simultaneous task count? Analysis of the driver logs during these tests reveals that the count parameter in UserProcessBundledParallelTasks is consistently 1, even under h
Topic:
App & System Services
SubTopic:
Drivers
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