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    SubjectRe: [PATCH] O_STREAMING - flag for optimal streaming I/O
    On Tue, Oct 08, 2002 at 01:03:11PM -0700, Andrew Morton wrote:
    > Matthias Schniedermeyer wrote:
    > >
    > > ...
    > > I only have 3 GB of RAM, and creating and writing trashes the whole
    > > cache twice.
    >
    > That's actually something completely dumb and irritating which
    > Linux has done for ever ;)
    >
    > What we need is to detect the situation where someone is linearly
    > walking through a file which is preposterously too large to cache,
    > and just start dropping it.
    >
    > It's not hard to implement the lower machinery to do that - it would
    > basically be an internal call to posix_fadvise(), which we don't
    > have but could and perhaps should...
    >
    > The tricky part is designing the algorithm which decides when to
    > pull the trigger.

    I have more of this cases.

    I use a program called VDR. This is for recording digital-TV-program
    from satallite.

    After a recording is finished i cut the recordings. I my case i "stream"
    the input-data via NFS from the recording machine(s) through a converter
    into the local temporary directory. After i have enough files i create
    ISO-images of the files. When i create an ISO-images i "stream" the
    files from HDD1 to HDD2 because otherwise it would completly kill the
    performance. Then i burn the ISO-Image onto a DVD-R.


    Every single part in the whole process trashes the cache.




    Bis denn

    --
    Real Programmers consider "what you see is what you get" to be just as
    bad a concept in Text Editors as it is in women. No, the Real Programmer
    wants a "you asked for it, you got it" text editor -- complicated,
    cryptic, powerful, unforgiving, dangerous.

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