lkml.org 
[lkml]   [2006]   [Apr]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRE: [PATCH] likely cleanup: revert unlikely in ll_back_merge_fn
    Date
    It seems that new BIOs do not have BIO_SEG_VALID set. So when you do sequential IO, the IO being back-merged should always have not
    had valid segments.

    I ran bonnie++ and it shows the same thing.

    > Well you'd want to optimize for the busy case, right, no
    > point in optimizing for a more idle system.
    >
    > I'm not at all uninterested in this, I'd just like to see a
    > more intelligent/controlled work load that actually stresses
    > the io subsystem being profiled. If you have a not-so-busy
    > system, you like don't do enough IO to trigger a lot of
    > merges. Or maybe you do, and we just have a bug somewhere so
    > that we unfortunately repeatedly recount segments.
    >
    > Care to run a simple io benchmark and profile that?
    >
    > --
    > Jens Axboe
    >

    -
    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: 2006-04-25 23:41    [W:2.513 / U:0.204 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site