lkml.org 
[lkml]   [2007]   [Nov]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: -rt doesn't compile for UML
    From
    Date
    > > When writing a big file to a ubd disk, everything in uml slows down to
    > > a crawl, even though CPU usage is minimal.
    >
    > What exactly is your test case?

    Something like:

    dd if=/host/tmp/bigfile of=/tmp/bigfile bs=1048576 count=100

    and run 'top' or 'watch something' in another terminal, which
    sometimes completely stops updating during the write.

    > I have some patches which theoretically should help I/O performance
    > which I've been sitting on because I can't find a case where they
    > help.

    It's not I/O performance I'm worried about, but scheduling latencies.
    CPU use inside and outside the UML is minimal, so I can't see where
    this slowdown comes from.

    Miklos
    -
    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: 2007-11-28 16:37    [W:0.020 / U:90.000 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site