From mboxrd@z Thu Jan  1 00:00:00 1970
From: Coly Li <colyli@suse.de>
Subject: Re: [RFC PATCH 1/2] RAID1: a new I/O barrier implementation to remove
 resync window
Date: Wed, 30 Nov 2016 15:19:46 +0800
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To: Guoqing Jiang <gqjiang@suse.com>, linux-raid@vger.kernel.org
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On 2016/11/30 下午2:37, Guoqing Jiang wrote:
> 
> 
> On 11/28/2016 03:33 PM, Coly Li wrote:
>> In raid1_sync_request(), I see,
>> conf->cluster_sync_low = mddev->curr_resync_completed;
>> conf->cluster_sync_high = conf->cluster_sync_low +
>> CLUSTER_RESYNC_WINDOW_SECTORS;
>>
>> Is it possible that LBA range [conf->cluster_sync_low,
>> conf->cluster_sync_high] goes across the border of a barrier unit size ?
> 
> Not pretty sure about it, but since cluster's resync window is 32M which is
> less than BARRIER_UNIT_SECTOR_SIZE, I guess it would not cause trouble.

Thanks for the hint. So BARRIER_UNIT_SECTOR_SIZE is 32MB aligned,
cluster's resync window won't go across the boundary.


Coly