On 21/06/2023 09:05, Xiao Ni wrote:
Cool. And I noticed you mentioned 'fast path' in many places. What's the meaning of 'fast path'? Does it mean the path that i/os are submitting?
It's a pretty generic kernel term, used everywhere. It's intended to be the normal route for whatever is going on, but it must ALWAYS ALWAYS ALWAYS be optimised for speed.
If it hits a problem, it must back out and use the "slow path", which can wait, block, whatever.
So the idea is that all your operations normally complete straight away, but if they can't they go into a different path that guarantees they complete, but don't block the normal operation of the system.
Cheers, Wol
