Re: [RFC PATCH] fs/exec: Add the support for ELF program's NUMA replication
From: Huang Shijie
Date: Wed Sep 08 2021 - 21:48:41 EST
On Mon, Sep 06, 2021 at 11:35:01AM +0200, David Hildenbrand wrote:
> On 06.09.21 18:16, 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.
> Am I missing something important or is this just absolutely not what we
Please see the thread:
Linus did not think it is a good choice to implement the "per-numa node page cache"
> This means that for each and every invocation of the binary, we'll COW the
> complete binary -- an awful lot of wasted main memory and swap.
Only the one who cares about the performance in NUMA will use this interface.
Most of the people never use it..