lkml.org 
[lkml]   [2006]   [Sep]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [Feature] x86_64 page tracking for Stratus servers
    Date

    > Silly question, why can't you do all this from stop_machine_run context (or
    > your SMI) that doesn't have to worry about other CPUs dirtying memory?

    Because that would be too slow for continuous mirroring.

    You can't go through 10+GB of virtual memory (or more with shared
    memory because the scan has to be virtual) in an interrupt.

    The only sane way is to do it continuously.

    > [*] Though if it gets included, it would not stop me lamenting the
    > proliferation of complexities to support *tiny* obscure userbases. Can
    > we wait until your hardware is smart enough to snoop the cc? :)


    My guess is that if we had a generic memory mirror subsystem other people would
    find uses for it too. e.g. a lot of systems support spare DIMMs these days and mirroring
    some memory to it seems like a smart idea. That means normally the hardware
    does it, but perhaps some stuff can be done better by doing it in software.

    Or it is also a bit similar to the algorithms Xen uses for live migration.
    If that was implemented on the kernel level something like this might
    be useful too. I think OpenVZ has some kind of migration support, but it's
    currently not live.

    -andi

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2006-09-06 09:41    [W:0.021 / U:150.076 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site