Re: [PATCH] mm/mempolicy: add sysfs interface to override NUMA node bandwidth

[Yee Li <seven.yi.lee@gmail.com>]

Hi Joshua,

Thanks for your feedback and kind wishes.

> I just wanted to touch on this. Is this true? Weighted interleave already
> exposes sysfs that lets the user set the weights they want. On one hand
> I think it would be helpful for there to be a tool to see what the
> effects of setting bandwidth information on a system could be, if it
> had other side effects. I'm not sure if there is a strong case to do this
> purely for weighted interleave auto-tuning, which already has a manual
> weight override and pretty simple calculations : -)

I agree — writing a small userspace tool to compute the weights based on
actual measured bandwidths (from mlc or stream) is a really good approach.

> Thank you for the helpful clarification. Just to be sure, are there
> other intended things that the user can test other than what weights
> weighted interleave would resolve to?

We can continue DRAM + CXL weighted interleave performance testing 
later, following Gregory Price's experiments [1].
[1] Link:
https://lore.kernel.org/linux-mm/20240103224209.2541-1-gregory.price@memverge.com/