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Date: Tue, 24 Jan 2017 18:48:36 -0800
From: Matthew Wilcox <willy@infradead.org>
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>,
        zhouxianrong <zhouxianrong@huawei.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>, linux-mm@kvack.org,
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Subject: Re: [PATCH] mm: extend zero pages to same element pages for zram
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On Wed, Jan 25, 2017 at 10:32:44AM +0900, Sergey Senozhatsky wrote:
> 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

what?  memset ONLY HANDLES BYTES.

I pointed this out earlier, but you don't seem to be listening.  Let me
try it again.

MEMSET ONLY HANDLES BYTES.