lkml.org 
[lkml]   [2006]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] fs : reorder some 'struct inode' fields to speedup i_size manipulations
    On Mon, 27 Nov 2006 22:52:04 +0100
    Eric Dumazet <dada1@cosmosbay.com> wrote:

    > > I didn't understand that paragraph at all, really, so I took it out.
    > >
    > > At present an i_size change will dirty one, two or three cachelines, most
    > > likely one or two.
    > >
    > > After your patch an i_size change will dirty one or two cachelines, most
    > > likely one.
    > >
    > > yes?
    >
    > nope
    >
    > Before :
    > ---------
    > offsetof(i_size) = 0x3C
    >
    > i_size is 8 bytes, so i_size spans 2 cache lines (if 64 or 32 bytes cache lines)

    This all depends on the offset of the inode, and you don't know what that is.

    offsetof(ext3_inode_info, vfs_inode) != offsetof(nfs_inode, vfs_inode), etc.
    -
    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: 2006-11-27 23:05    [W:2.604 / U:0.056 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site