Re: [LSF/MM/BPF TOPIC] mshare - sharing page tables across processes

[Isaac Manjarres <isaacmanjarres@google.com>]

On Wed, Feb 25, 2026 at 04:59:32PM -0800, Kalesh Singh wrote:
> On Mon, Feb 23, 2026 at 6:12 PM <anthony.yznaga@oracle.com> wrote:
> >
> > mshare is a new form of shared memory that shares resources between
> > processes, namely the page tables entries and VMAs of the shared
> > objects. Advantages include reduced memory consumption through
> > eliminating the need for duplicated PTEs in each process, reduced
> > overhead needed to fault shared pages into multiple processes, and the
> > ability for updates to the memory such as protection changes to be
> > immdediately visible to all sharing processes.
> >
> > For some time now the proposed API has continued to evolve. With
> > feedback from mm maintainers, a new approach using syscalls is being
> > taken to create, attach, and deattach mshare regions and to map and
> > manipulate the memory objects within a region.
> >
> > Let's discuss the current state of the API and technical challenges of
> > managing and accomodating shared page tables in the kernel.
> >
> > Anthony
> >
> >
> > References:
> >
> > https://lore.kernel.org/linux-mm/20250820010415.699353-1-anthony.yznaga@oracle.com/
> > https://lore.kernel.org/linux-mm/20250404021902.48863-1-anthony.yznaga@oracle.com/
> 
> Hi Anthony,
> 
> I would be very interested in participating in this discussion at LSF/MM.
> 
> As mentioned on the mailing list, we are currently exploring similar
> optimizations to deduplicate page tables for Android's Zygote process.
> I'd love to join the session to discuss how the proposed sharing
> mechanisms might align.
> 
> Thanks,
> Kalesh

Hello Anthony,

I'm also working on optimizing pagetable usage in Android with Kalesh,
so I'm definitely interested in participating in this discussion as
well.

Thanks,
Isaac