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    SubjectRe: [PATCH] O_STREAMING - flag for optimal streaming I/O
    On Thu, Oct 10, 2002 at 12:55:08PM +0200, Helge Hafting wrote:
    > Mark Mielke wrote:
    > > I might be wrong, but it seems to me that O_STREAMING isn't the answer
    > > to everything. The primary benefactors of O_STREAMING would be
    > > applications that read very large files that do not fit into RAM, from
    > > start to finish.
    > It don't have to be a file that don't fit into RAM. Remember, other
    > running apps wants memory and cache too, so the "fair share" of memory
    > for _this_ process is much smaller than all of RAM.
    > So, O_STREAMING makes sense for all files where we know that we're going
    > sequentially and that caching this for long won't help.
    > (Because the contents likely will be pushed out before we need
    > them again anyway (DVD case) or we know were going to delete
    > the file, or we simply don't want to push anything else
    > out even if we could cache this.)

    Then perhaps O_STREAMING should be called O_EXTENDEDSTREAMING.

    If you overload O_STREAMING to contain all possibile uses for sequential
    reads, you end up hurting yourself.

    Small files are different beasts from large files. If you want O_STREAMING
    to work in all cases, you really want standard mode to work in all cases,
    and O_STREAMING is not for you.

    mark

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