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Date: Wed, 24 Aug 2016 10:04:15 +0900
From: Minchan Kim <minchan@kernel.org>
To: Hui Zhu <zhuhui@xiaomi.com>
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Subject: Re: [RFC 0/4] ZRAM: make it just store the high compression rate page
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Hi Hui,

On Mon, Aug 22, 2016 at 04:25:05PM +0800, Hui Zhu wrote:
> Current ZRAM just can store all pages even if the compression rate
> of a page is really low.  So the compression rate of ZRAM is out of
> control when it is running.
> In my part, I did some test and record with ZRAM.  The compression rate
> is about 40%.
> 
> This series of patches make ZRAM can just store the page that the
> compressed size is smaller than a value.
> With these patches, I set the value to 2048 and did the same test with
> before.  The compression rate is about 20%.  The times of lowmemorykiller
> also decreased.

I have an interest about the feature for a long time but didn't work on it
because I didn't have a good idea to implment it with generic approach
without layer violation. I will look into this after handling urgent works.

Thanks.