lkml.org 
[lkml]   [2001]   [Nov]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: Swap
    Dan Maas wrote:
    >
    > > Uhhhh, read his original mail. When using mmap() he had
    > > problems with the VM doing bad page replacement, while
    > > read() was smooth.
    >
    > I should add that I did experiment with madvise(MADV_SEQUENTIAL) on the
    > mapping, and with madvise(MADV_WILLNEED) on pages about to be needed. These
    > had no effect. What *did* help with underruns was pre-touching each page in
    > a large block (120KB), before sending that block to the output device. At
    > that point I thought the mmap() code was getting to be more complicated that
    > it was worth so I just dropped back to read()...

    There's a new system call, sys_readahead() which does what you want.

    It would be nice to make the pagein code smarter though.

    -
    -
    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: 2005-03-22 13:13    [W:0.022 / U:31.392 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site