lkml.org 
[lkml]   [2001]   [Mar]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    Hi,

    On Wed, Mar 07, 2001 at 09:15:36PM +0100, Jens Axboe wrote:
    > On Wed, Mar 07 2001, Stephen C. Tweedie wrote:
    > >
    > > For most fs'es, that's not an issue. The fs won't start writeback on
    > > the primary disk at all until the journal commit has been acknowledged
    > > as firm on disk.
    >
    > But do you then force wait on that journal commit?

    It doesn't matter too much --- it's only the writeback which is doing
    this (ext3 uses a separate journal thread for it), so any sleep is
    only there to wait for the moment when writeback can safely begin:
    users of the filesystem won't see any stalls.

    > A barrier operation is sufficient then. So you're saying don't
    > over design, a simple barrier is all you need?

    Pretty much so. The simple barrier is the only thing which can be
    effectively optimised at the hardware level with SCSI anyway.

    Cheers,
    Stephen
    -
    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 13:29    [W:0.024 / U:58.668 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site