lkml.org 
[lkml]   [1999]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: 2.2.0-pre[56] swap performance poor with > 1 thrashing task


    On Fri, 8 Jan 1999, Benjamin Redelings I wrote:
    >
    > Maybe this is not really a problem with swapping, but more with
    > concurrent I/O in general,

    It's really easy to get really crappy performance with concurrent IO, if
    you end up just seeking back and forth on the disk - which is why we
    should be trying to cluster our IO. Sounds like we end up with silly
    behaviour where one process is paging in from one area of the disk while
    the other is paging out to another area, resulting in all the time spent
    in just moving the disk head rather than moving any actual data.

    Or something silly like that. The fix is probably not all that complex:
    the code is supposed to try to avoid it, but I bet I just had some idiotic
    braino that just completely defeated the whole idea. It sounds like Zlatko
    found my braino already.

    Linus


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

    \
     
     \ /
      Last update: 2005-03-22 13:49    [W:2.236 / U:0.032 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site