Mark Lord

I actually ran into this myself last fall, when I got a new notebook computer and then tested various NVMe drives for use with it. There are existing Linux utilities to do various configurations of multi-threaded I/O benchmarks, and they do it reasonably well. Eg. KDiskMark on KDE/Plasma, or the Gnome disk utility. The subject of benchmarking drives is sufficiently complex, I don't think it belongs in a low-level utility like hdparm, which is used on everything from small micro-controllers, RaspberryPi's,...

I dunno. I'm kinda torn by this request. How would an extreme multi-threaded read test measure anything relevant to Real Life? The existing -t flag is for measuring sequential read speed, giving an indication of the throughput that real apps might expect to achieve. Eg. KVM or virtualbox saving a multi-GB VM state. Doing simultaneous over-lapping runs of the exact same data blocks from the drive isn't going to be relevant, and might just end up with most threads reading from the on-drive cache, rather...

I dunno. I'm kinda torn by this request. How would an extreme multi-threaded read test measure anything relevant to Real Life? The existing -t flag is for measuring sequential read speed, giving an indication of the throughput that real apps might expect to achieve. Doing simultaneous over-lapping runs of the exact same data blocks from the drive isn't going to be relevant, and might just end up with most threads reading from the on-drive cache, rather than the flash memory.

Unfortunately, SATA Port Multipliers are surprisingly difficult. They never really got the "love" they deserved from chip makers and manufacturers, and the result is that getting FIS based switching (FBS) to work, end-to-end, is a rare thing. The chipset inside the port-multiplier itself (aka. "the dock"), and its firmware, both have to support FBS without any chip-specific quirks (aka. "secret bug fixes"). Then the host controller (the "card") also has to have FBS and NCQ support, and its firmware...

Unable to run multiple hdparm secure erase actions in parallel against multiple drives using port multiplier

Not all SATA Port-Multiplier chips are capable of running multiple commands simultaneously. That is likely the issue you see here -- hardware, not software. Command-Based-Switching (CBS) is the most common type, and those can only control a single drive at any point in time. FIS-Based-Switching (FBS) are the better kind of port-multipler, and those can treat each drive completely independently, with multiple commands in-flight to multiple drives simultaneously. Cheers

set-sector-size and -Istdout woes with TOSHIBA MG09ACA18TE

The datasheet clearly shows that only the models with an "S" as the 5th character support changing the sector size. Yours has an "A". Drive doesn't support it.