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Date: Wed, 25 Jan 2017 10:32:44 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Minchan Kim <minchan@kernel.org>
Cc: zhouxianrong <zhouxianrong@huawei.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>, linux-mm@kvack.org,
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        zhangshiming5@huawei.com, won.ho.park@huawei.com
Subject: Re: [PATCH] mm: extend zero pages to same element pages for zram
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Hello,

On (01/25/17 10:29), Minchan Kim wrote:
[..]
> > the result as listed below:
> > 
> > zero    pattern_char   pattern_short   pattern_int   pattern_long   total      (unit)
> > 162989  14454          3534            23516         2769           3294399    (page)
> > 
>
> so, int covers 93%. As considering non-zero dedup hit ratio is low, I think *int* is
> enough if memset is really fast. So, I'd like to go with 'int' if Sergey doesn't mind.

yep, 4 byte pattern matching and memset() sounds like a good plan to me

	-ss