Re: [RFC PATCH] fs/exec: Add the support for ELF program's NUMA replication

From: Matthew Wilcox
Date: Mon Sep 06 2021 - 08:10:48 EST


On Mon, Sep 06, 2021 at 04:16:13PM +0000, Huang Shijie wrote:
> This patch adds AT_NUMA_REPLICATION for execveat().
>
> If this flag is set, the kernel will trigger COW(copy on write)
> on the mmapped ELF binary. So the program will have a copied-page
> on its NUMA node, even if the original page in page cache is
> on other NUMA nodes.

This does absolutely nothing for programs which run on multiple NUMA
nodes at the same time.

Also, I dislike the abuse of the term "COW" for this. It's COF --
Copy On Fault.