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Edited 11 months ago
This is how a silently enabled kernel configuration can affect your system performance:

https://lore.kernel.org/stable/97397e8d-f447-4cf7-84a1-070989d0a7fd@amazon.com/T/#u

I fixed this at the beginning of this year, but did not backport to stable trees. Luiz Capitulino from Amazon reported that this resulted in performance regression in their 6.1 kernels.

DEBUG_PREEMPT has been enabled by default since pre-git era for PREEMPT kernels, but distros that were using PREEMPT_VOLUNTARY silently enabled PREEMPTION and DEBUG_PREEMPT after the introduction of PREEMPT_DYNAMIC. And DEBUG_PREEMPT is better disabled for production kernels regardless of the preemption model used.
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