[dm-devel] Re: Too many I/O controller patches

[Hirokazu Takahashi <taka valinux co jp>]

Hi,

> I think that OOM problems caused by memory/cache systems.
> So, it will be better that I/O controller created out of these problems
> first, although a lateness of the I/O device would be related.
> If these problem can be resolved, its technique should be applied into 
> normal I/O control as well as cgroups.

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.

> Buffered write I/O is also related with cache system.
> We must consider this problem as I/O control.
> I don't have a good way which can resolve this problems.
> 

Thank you,
Hirokazu Takahashi.