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    SubjectRe: [RFC] Union Mount: Readdir approaches
    On Fri, Sep 07, 2007 at 04:31:26PM +0900, wrote:
    > When the first readdir is issued:
    > - call vfs_readdir for every underlying opened dir (file) object.
    > - store every entry to either the hash table for the result or the
    > whiteout, when the same-named entry didn't exist in the tables.
    > - to improvement the performance, the allocated memory for the hash
    > tables are managed in a pointer array. and the elements are
    > concatinated logically by the pointer.
    > - the pointer for the result-table, the version, and the currect jiffies
    > are set to vdir, which is a cache in an inode.
    > - all cache are copied to a member in a file object.
    > - the index of the cache memory block and the offset in an array is
    > handled as the seek position.

    Ok, interesting approach. So you define the seek behaviour on your
    directory cache rather than allowing the underlying filesystems to
    interpret the seek. I guess we can do something similar with Union
    Mounts also.

    > If you are interested in this approach, please refer to
    > It is working and used by several people.

    Will look at it. And thanks Junjiro for your detailed explanation of
    the aufs approach.

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      Last update: 2007-09-07 10:01    [W:0.022 / U:7.824 seconds]
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