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    SubjectRe: [RFC] PATCH 0/4 - Time virtualization
    On Wed, Apr 19, 2006 at 02:25:00AM -0600, Eric W. Biederman wrote:
    > That patch should probably be separated, from the rest.
    > But it looks like a fairly sane idea.

    Yeah, I'll keep these together for now, but the ptrace one is
    conceptually different from the rest.

    > I think you missed a couple essential things to a time namespace.
    > Timers. The posix timers, in particular. The worst
    > of those is the monotonic timer.

    Oops, thanks for pointing that out.

    > In the case of migration the ugly case to properly handle is the
    > monotonic timer. That needs an offset yet it is absolutely forbidden
    > to provide that offset from the inside. So this is the one namespace
    > that I think is inappropriate to use sys_unshare to create.
    > We need a system call so that we can specify the minimum or the
    > starting monotonic time base.

    For migration, it looks like the container will have to specify the
    time base at creation so that everything in it will have a consistent
    view of time if they get moved around.

    So, maybe it belongs in clone as a "backwards" flag similar to
    CLONE_NEWNS.

    Jeff
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