[lkml]   [1999]   [Feb]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: fsync on large files

    On Mon, 15 Feb 1999, Theodore Y. Ts'o wrote:
    > So you mean moving the dirty list into the filesystme-generic portion of
    > the inode structure, instead of being an ext2-specific hack? That seems
    > quite reasonable.


    > list. What I'm currently thinking about is to make the filesystem
    > allocate memory for storing the dirty list, and allow the filesystem
    > decide what an appropriate number of blocks to allow to be stored in the
    > dirty list. Most files never have fsync() called upon them, so a way we
    > can make things efficient is to only create the dirty list after the
    > first call to fsync() on an inode. The first fsync() can then either go
    > through all of the indirect blocks, or cause a forced fsync_dev if that
    > would be more efficient. That way, for files which don't get
    > fsync()'ed, we don't have the overhead of keeping and maintaining the
    > dirty list.
    > Does this sound like a reasonable design?


    I'd much rather just always add it to the "inode dirty list". List
    maintenance is essentially zero overhead if you use the nice list macros
    in <linux/list.h> (as opposed to the braindamaged BSD compatibility macros
    in <linux/lists.h>), and it's fairly trivial to just keep each dirty block
    on two dirty lists (one inode-specific, one global - you'd still use the
    global one for normal write-outs).

    It's just a few pointer operations, and the advantage of having a clean
    and simple design probably results in better performance anyway.


    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:50    [W:0.020 / U:62.996 seconds]
    ©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site