From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joseph Qi <joseph.qi@huawei.com>
Date: Fri, 25 Sep 2015 09:53:36 +0800
Subject: [Ocfs2-devel] [RFC] ocfs2: a method to prevent lock on the
 blocked queue is starved.
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To: ocfs2-devel@oss.oracle.com

Simply switch converting list and blocked list cannot resolve the
starvation case fundamentally.
Maybe we have to set a deadline and bring in a scheduler strategy.
@Junxiao, do you have any other idea?

On 2015/8/27 20:11, jiangyiwen wrote:
> In dlm_shuffle_lists, if there are conversions still blocked on the
> converting queue all the time, the blocked locks on the blocked queue
> can never be processed, so the locks on the blocked queue will be
> starved.
> 
> So I have an idea to solve this problem: To switch the priority between
> the converting queue and blocked queue, i.e. process the locks on the
> blocked queue first. In this way, the lock on the blocked queue will
> be processed and it will not enter the blocked queue until the
> lockres is purged. so the scenario above will be solved.
> 
> Anyone has better ideas or advices?
> 
> Thanks,
> Yiwen Jiang
> 
> 
> .
>