Feature req: cryptsetup_ option for perf-no_read_workqueue & perf-no_write_workqueue

[selckin]

See https://wiki.archlinux.org/title/Dm-crypt/Specialties#Disable_workqueue_for_increased_solid_state_drive_(SSD)_performance

[desultory]

do you think there is value in having it be a toggle? Looking into that, I think you can enable it once with the --persistent flag, so that config option is in the luks header itself. If ugrd were handling this, I don't think it should set it persistently, so it would mostly make sense as a toggle. Do those toggles have an equivalent to enable those queues?

To implement this, it would be as simple as a global or per-device config option that appends to the cmdline string, like this:

https://github.com/desultory/ugrd/blob/main/src/ugrd/crypto/cryptsetup.py#L490-L491

[selckin]

Indeed when I was reading it, I thought/assumed it worked the same way as the discard (cryptsetup_trim) option (that you also linked), so went looking for an option for the queues aswel.

I like having it in the config that I can backup & copy to not forget next time, and easily toggle to test.
(Some more background: as a cryptsetup rookie, the wiki commands (wrongly) asked for a password and i didn't know how to tell it to use my yubikey gpg, so I thought lets just enable it in ugrd like trim)

But as you say, it is not necessary

[desultory]

even it not necessary, I can see a reason to add it especially if it's something people may need to toggle in certain cases, especially if it causes issues. It could potentially be a cmdline arg as well, if there is any reason it would need to be toggled at boot time. The config would bake it into the image, but it could be config and a kernel cmdline arg. It may have to be 2 for both reads/writes.