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    SubjectRe: [PATCH 07/10] Increase compressed page size threshold
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    Hi Nitin,

    On Mon, Aug 9, 2010 at 8:26 PM, Nitin Gupta <ngupta@vflare.org> wrote:
    > Compression takes much more time than decompression. So, its quite
    > wasteful in terms of both CPU cycles and memory usage to have a very
    > low compressed page size threshold and thereby storing such not-so-well
    > compressible pages as-is (uncompressed). So, increasing it from
    > PAGE_SIZE/2 to PAGE_SIZE/8*7. A low threshold was useful when we had
    > "backing swap" support where we could forward such pages to the backing
    > device (applicable only when zram was used as swap disk).
    >
    > It is not yet configurable through sysfs but may be exported in future,
    > along with threshold for average compression ratio.
    >
    > Signed-off-by: Nitin Gupta <ngupta@vflare.org>

    The description makes sense but lacks any real data. What kind of
    workloads did you test this with? Where does it help most? How much?

    Pekka


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