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From: Jukka Zitting <jukka.zitting@gmail.com>
Date: Wed, 17 Feb 2010 15:34:53 +0100
Message-ID: <510143ac1002170634l4c8f263an640c14c09162ac45@mail.gmail.com>
Subject: Re: Casandara and Jackrabbit
To: users@jackrabbit.apache.org
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Hi,

On Wed, Feb 17, 2010 at 11:53 AM, Ian Boston <ieb@tfd.co.uk> wrote:
> On 17 Feb 2010, at 10:43, Jukka Zitting wrote:
>> I'm not aware of anything like that, though there's been some
>> discussion about persistence on top of distributed databases or hash
>> tables. The main problem with such approaches is the eventual
>> consistency model that can be troublesome for the current Jackrabbit
>> architecture.
>
> Is that because, in a cluster one JR node might get an event that an
> Item exists, but its not yet present on the backend its connected to,
> and there are no guarantees over the order in which items appear,
> so, for instance, the hierarchy manager might find a child but not
> the parent?

Exactly. The current Jackrabbit architecture assumes that the
underlying persistence store is always (not just eventually)
consistent.

> Do you have any pointers to the discussions so I can go and read ?

It's been mostly coffee room discussions so far, but I'll bring up the
topic soon on dev@ as a part of a larger Jackrabbit 3 roadmap
discussion.

BR,

Jukka Zitting