NVMe Tuning

[Arwen]

I have tried to follow the Wiki section to set the power profile of the NVMe SSD.
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This seems to work until a reboot when it defaults back to profile 0.

Is there a command missing to save it to the NVMe?
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Yes, there does appear to be a command missing to make it persistant across reboots & power cycles.
I think this is what we are looking for;

Code:

-s, --save
   Save the attribute so that it persists through all power states and resets.

So the command in both the example and your case is probably;

Code:

$ sudo nvme set-feature /dev/nvme0 -f 2 -v 2 -s

Whence someone has tested that, I'll update the Wiki and remove the note about the non-persistant nature I just added.

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Also after googling to try and find how to make NVMe setting persistant, I found some references to enabling Autonomous Power State Transistion rather than editing the power management.
Which is the correct one to use APST (feature 0x0c) or Power Managment (feature 2) and how to make these setting persistent?

I don't know anything about APST / Autonomous Power State Transistion.