RE: [LKP] Re: [x86/mce] 1de08dccd3: will-it-scale.per_process_ops -14.1% regression

[Luck, Tony]

	0000000000019260 D pqr_state

Do you have /sys/fs/resctrl mounted?  This variable is read on every context switch.
If your benchmark does a lot of context switching and this now shares a cache line
with something different (especially something that is sometimes modified from another
CPU) that could cause some cache line bouncing.

-Tony