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Subject: Re: [PATCH] ocfs2: avoid getting dlm lock of the target directory
 multiple times during reflink process
To:     Gang He <ghe@suse.com>, mark@fasheh.com, jlbec@evilplan.org
Cc:     linux-kernel@vger.kernel.org, ocfs2-devel@oss.oracle.com,
        akpm@linux-foundation.org
References: <20210826075941.28480-1-ghe@suse.com>
 <744d756c-7640-d312-37ef-126755324e8a@suse.com>
From:   Joseph Qi <joseph.qi@linux.alibaba.com>
Message-ID: <abe27a3a-efde-660c-4d9c-d659eba3eab1@linux.alibaba.com>
Date:   Tue, 31 Aug 2021 15:39:59 +0800
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On 8/31/21 2:25 PM, Gang He wrote:
> Hello Joseph and Wengang,
> 
> When you have time, please help review this patch.
> About the deadlock problem which was caused by ocfs2_downconvert_lock failure, we have the fix patch, it is very key.
> But I feel this patch is still useful as a optimization patch, the user
> case is to reflink the files to the same directory concurrently, our users usually backup the files(via reflink) from the cluster nodes concurrently(via crontab) every day/hour.
> The current design, during the reflink process, the node will acquire/release dlm lock of the target directory multiple times,
> this is very inefficient in concurrently reflink.
> 

Sure, I'll spend some time this week.

Thanks,
Joseph