Comment 7 for bug 1563505

David, thanks for providing more information!

In terms of looking for issues related to the NVMe driver, this is probably the best approach:

dmesg | grep -i nvme

And then see if there is anything suspicious in the resulting output.

In term of the CPU performance being dramatically different between AC and battery, in my experience with the intel_pstate CPU frequency scaling driver, the performance should be the same. But we'll double-check our findings on this as there could have always been regressions or changes in Stable Release Updates (SRUs) in Ubuntu since we last thoroughly tested this aspect.

Would you say Firefox is the primary application you're using when you encounter this issue?

Thanks!