From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Xu <peterx@redhat.com>
Subject: Re: [PATCH 06/12] migration: do not detect zero page
 for compression
Date: Tue, 19 Jun 2018 15:30:34 +0800
Message-ID: <20180619073034.GA14814@xz-mi>
References: <20180604095520.8563-1-xiaoguangrong@tencent.com>
	<20180604095520.8563-7-xiaoguangrong@tencent.com>
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	Xiao Guangrong <xiaoguangrong@tencent.com>, dgilbert@redhat.com,
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On Mon, Jun 04, 2018 at 05:55:14PM +0800, guangrong.xiao@gmail.com wrote:
> From: Xiao Guangrong <xiaoguangrong@tencent.com>
> 
> Detecting zero page is not a light work, we can disable it
> for compression that can handle all zero data very well

Is there any number shows how the compression algo performs better
than the zero-detect algo?  Asked since AFAIU buffer_is_zero() might
be fast, depending on how init_accel() is done in util/bufferiszero.c.

>>From compression rate POV of course zero page algo wins since it
contains no data (but only a flag).

Regards,

-- 
Peter Xu