linux-kernel - Re: [PATCH] mm: extend zero pages to same element pages for zram

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Message-ID: <20170125013244.GB2234@jagdpanzerIV.localdomain>
Date:   Wed, 25 Jan 2017 10:32:44 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>
To:     Minchan Kim <minchan@...nel.org>
Cc:     zhouxianrong <zhouxianrong@...wei.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>,
        Joonsoo Kim <iamjoonsoo.kim@....com>, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
        sergey.senozhatsky@...il.com, ngupta@...are.org,
        Mi.Sophia.Wang@...wei.com, zhouxiyu@...wei.com,
        weidu.du@...wei.com, zhangshiming5@...wei.com,
        won.ho.park@...wei.com
Subject: Re: [PATCH] mm: extend zero pages to same element pages for zram

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