Yes, this is one of the problems linux kernel still has, which should
be solved.
But I believe this should be done in the linux memory management layer
including the cgroup memory controller, which has to work correctly
on any type of device with various access speeds.
I think it's better that I/O controllers should only focus on flow of
I/O requests. This approach will keep the implementation of linux
kernel simple.
Thank you,
Hirokazu Takahashi.
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