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From Antony Blakey <antony.bla...@gmail.com>
Subject Re: Why sequential document ids? [was: Re: What's the speed(performance) of couchdb?]
Date Mon, 02 Mar 2009 23:13:02 GMT

On 03/03/2009, at 9:26 AM, Dean Landolt wrote:

> I can see the point of replication source, but document origination  
> source
> is different than replication source, isn't it?

You are right. However the document origination source is required for  
a useful version vector, because you can then track which peer has how  
much of a source's writes. Which is useful if the source disappears.  
You can then build a distributed picture of the eventual consistency  
status.

> Yes.

I guess it's a tradeoff between wanting a distributed overview and  
wanting global anonymity. Maybe that's a valid configuration option,  
rather than being policy.

Unless a node makes it's identity available in some way other than  
replication, the source is still anonymous because there's no mapping  
of node id to source URL (which might change in any case). To identify  
the node you'd have to find the node, try to replicate from it, and  
get lucky that the id it provides is the one you're looking for.

Antony Blakey
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