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    SubjectRe: [RFC] Heads up on sys_fallocate()
    On Mon, 5 March 2007 00:32:14 +0000, Anton Altaparmakov wrote:
    >
    > I don't know how your compression algorithm works [...]

    LogFS is designed for flash media, so it does not have to worry much
    about reducing disk seeks. It is log-structured, which simplifies
    compression further.

    When writing a block, it basically compresses it and appends it to the
    log. Writes only have to be byte-aligned, so no space is lost for
    padding.

    The bad news for posix_fallocate() is that even if libc is smart enough
    to write random data, mmap() can still cause problems. If the VM
    decides to write a given page twice, the second write compresses better
    and the medium has filled up between the two writes, the users will have
    fun.

    Jörn

    --
    Joern's library part 9:
    http://www.scl.ameslab.gov/Publications/Gus/TwelveWays.html
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