A thought just occurred to me. It is quite possible, that from the perspective of the NG routing algorithm - that it will be preferable to send a request to a poorly suited node to whom a connection is already open, than to a well suited node to which we would need to establish a connection.
Why is this bad? Well, NG would be making a perfectly sensible and rational decision given that its goal is to minimize the time required to retrieve the data for *this* request, but it doesn't account for the fact that the establishment of a connection will benefit future requests. How do we fix it? Well, the hard way would be to try to factor in the future benefits of opening a connection to this node into this routing request. This would make things a bit messy as much of NG's elegance comes from the simplicity of the thing it is trying to minimize (how long will it take to get the data), but it would probably be doable (perhaps subtract, from the cost of establishing the connection, the estimated future time savings based on the average number of messages per connection). Fortunately, a much easier way would be to simply say that all nodes in the RT must already have connections opened to them the moment they enter the routing table. If such a connection cannot be established, then the node in question is ignored in routing decisions and perhaps removed from the datastore altogether. There are several things that make this a better idea in NG than it might have been in the past: Firstly, NG should be able to get by with much fewer references (30-50 at a guess, but we will need to experiment). The reason is that the fewer references, the faster our node will collect information on each individual reference - so too many references could actually be bad for NG routing. Secondly, with NIO the cost of idle connections has been greatly reduced in-terms of threads (and therefore CPU and memory usage). This will also serve to decrease any performance slowness for the user's first few requests which will otherwise be delayed as we establish connections. So hopefully that is problem solved for that issue, although it does raise a more general question of whether there are other areas in which NG Routing's lack of a "big picture" could be problematic. I can't think of any, and perhaps there aren't any - but we should be vigilant. Ian. -- Ian Clarke [EMAIL PROTECTED] Coordinator, The Freenet Project http://freenetproject.org/ Founder, Locutus http://locut.us/ Personal Homepage http://locut.us/ian/
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