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Date: Wed, 24 Feb 2010 05:11:40 +0000
Message-ID: <8bc75ecf1002232111n22538dcbj7d68519bb1bfb5e8@mail.gmail.com>
Subject: Re: how to lock one-of-many ?
From: Martin Waite <waite.134@googlemail.com>
To: zookeeper-user@hadoop.apache.org
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Thanks Ted.   The randomization should work well in this case.

regards,
Martin

On 23 February 2010 18:27, Ted Dunning <ted.dunning@gmail.com> wrote:

> I think that the crux of Mahadev's suggestion is that you do as you say,
> but
> you should try the resources in randomized order.
>
> That will have very robust properties, especially with more than a handful
> of resources and is easy to code and to analyze.
>
> It won't work if you really mean "lock first available from this sequence".
>
> On Tue, Feb 23, 2010 at 4:05 AM, Martin Waite <waite.134@googlemail.com
> >wrote:
>
> > For locking, I could loop through
> > the available ids, attempting to create a lock for that in the locked
> > directory.  However this seems a bit clumsy and slow.  Also, the locks
> are
> > held for a relatively short time (1 second on average), and by time I
> have
> > blundered through all the possible locks, ids that were locked at the
> start
> > might be available by time I finished.
> >
>
>
>
> --
> Ted Dunning, CTO
> DeepDyve
>

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