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

[Gregory Price]

On Thu, Mar 12, 2026 at 05:12:07PM +0800, YeeLi wrote:
> From: yeeli <seven.yi.lee@xxxxxxxxx>
> 
> If the bandwidth reported by firmware or the device deviates from the
> actual measured bandwidth, administrators also lack a clear way to adjust
> the per-node weight values.
> 

If userland is setting the raw bandwidth stat, why can't they do a tiny
bit of math to figure out the preferred weighting and just write the
weights?

> 
> Userspace can write a single bandwidth value (in MB/s) to override both
> read_bandwidth and write_bandwidth for the corresponding NUMA node. The
> value is then propagated to the internal node_bw_table via
> mempolicy_set_node_perf().
> 
> This interface is intended for debugging and experimentation only.
> 

Should be posted as [RFC] then, I don't think we want this upstream.

~Gregory