Re: [PATCH v3] zram: extend zero pages to same element pages

From	Joonsoo Kim <iamjoonsoo.kim@lge.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3] zram: extend zero pages to same element pages
Date	2017-01-23 07:10 +0100
Message-ID	<t2FZg-2Pp-9@gated-at.bofh.it> (permalink)
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On Mon, Jan 23, 2017 at 01:47:20PM +0900, Minchan Kim wrote:
> Hello,
> 
> When I look at first patch, I wanted to use increment loop but didn't
> tell to you because that small piece of code is no harmful for readbility
> to me so I want to keep author's code rather than pointing the trivial
> which is just matter of preference out.
> 
> Rather than readiblity, I suspect it might hurt performance and talked
> with Namhyung but we cannot find anything decremental loop is bad
> compared to incremental. Rather than, many articles have been said
> decrement loop is faster like zhouxianrong's mentiond although I don't
> think it makes marginal difference.
> 
> Joonsoo, why do you think incremental is faster?
> zhouxianrong, why do you think decrement loops makes cache problem?
> 
> I'm okay either way. Just want to know why you guys think about it.

Hmm... I guess that cache prefetcher works better for forward access
but I'm not sure.

Thanks.

Thread

[PATCH v3] zram: extend zero pages to same element pages Minchan Kim <minchan@kernel.org> - 2017-01-23 03:00 +0100
  Re: [PATCH v3] zram: extend zero pages to same element pages Joonsoo Kim <iamjoonsoo.kim@lge.com> - 2017-01-23 04:00 +0100
    Re: [PATCH v3] zram: extend zero pages to same element pages zhouxianrong <zhouxianrong@huawei.com> - 2017-01-23 04:50 +0100
      Re: [PATCH v3] zram: extend zero pages to same element pages Minchan Kim <minchan@kernel.org> - 2017-01-23 05:50 +0100
        Re: [PATCH v3] zram: extend zero pages to same element pages Joonsoo Kim <iamjoonsoo.kim@lge.com> - 2017-01-23 07:10 +0100
          Re: [PATCH v3] zram: extend zero pages to same element pages zhouxianrong <zhouxianrong@huawei.com> - 2017-01-23 07:20 +0100
            Re: [PATCH v3] zram: extend zero pages to same element pages Minchan Kim <minchan@kernel.org> - 2017-01-23 08:50 +0100

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