From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Mason <clmason@fusionio.com>
Subject: Re: [RFC] RCU Judy array with distributed locking for FS extents
Date: Mon, 3 Jun 2013 09:07:06 -0400
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Cc: Linux FS Devel <linux-fsdevel@vger.kernel.org>,
	David Woodhouse <David.Woodhouse@intel.com>,
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	Lai Jiangshan <laijs@cn.fujitsu.com>,
	Stephen Hemminger <shemminger@vyatta.com>,
	Alan Stern <stern@rowland.harvard.edu>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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Quoting Mathieu Desnoyers (2013-06-03 08:46:01)
> > Hi Mathieu,
> > 
> > One problem here is that XFS wants to allow duplicate keys in the tree.
> > This is possible with some modifications to the skiplist code, but I'm
> > not sure if it fits into your description above.
> 
> Are those segments that completely overlap, or partially overlap ?

I believe completely overlap.  On the skiplist side I'll make it
possible for either one.

> 
> > 
> > Regardless, it is worth trying out.  I'll pull my current code back into
> > userland and try out the userspace-rcu port (I had planned this anyway).
> > That way we can have a proper head-to-head benchmark ;)
> 
> Cool! Don't hesitate to ping me if I can be of any help.

Once I get into the userland rcu code I'll probably have more questions.

-chris