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    SubjectRe: [PATCH 0/1] cover-letter/lz4: Implement lz4 with dynamic offset length.
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     Hello,

    >> (Added cover letter to avoid much text in patch description)
    >>
    >> LZ4 specification defines 2 byte offset length for 64 KB data.
    >> But in case of ZRAM we compress data per page and in most of
    >> architecture PAGE_SIZE is 4KB. So we can decide offset length based
    >> on actual offset value. For this we can reserve 1 bit to decide offset
    >> length (1 byte or 2 byte). 2 byte required only if ofsset is greater than 127,
    >> else 1 byte is enough.
    >
    >So what happens if I compress the data on a system with no dyn
    >offset and then send it over the network to a machine which has
    >dyn offset? Or, say, I have a USB stick with a compression enabled
    >FS, store files on a dyn offset enabled PC and then mount that USB
    >stick on a machine with no dyn offset support. And vice versa.


    lz4_dyn is not an extension of LZ4 so there is no backward compatibility.
    Consider this as a different algorithm adapted from LZ4 for better compression ratio.

    Thanks
    Maninder Singh

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