ok so basicly a file lookup works by broadcasting to the network and anyone who has the file replies, the location is then cached locally and the next time the file is needed no broadcast is needed as it is in local cache? correct? The reason we dont really want to go with caching as a final solution is that it wont reduce toward an optimal solution over time, ideally files that are commonly used should no longer be located in nodes that dont use them, instead they should be located locally. Well thats the theory anyway, if this isnt the case i think it may still be useful doing the work to prove the point that it doesnt provide any great benefit. Im a little worried that there might be a sticking point with the current lookup scheme if there are multiple copies however. Im not quite sure how to get around consistancy if you want to guarentee that every write accesses the most recent copy only. I can see this as a serious problem. Im not too sure how to get around it but i will have a think about it. I personally think that they would get a better performance benefit by breaking the file down into small pieces and spreading them over the network to get better read performance from the network as there are more hosts doing small amounts of disk IO each, i suppose this is similar to your stripe? However the acedemics in the department all seem very sold on the migration idea. personally i come from a RAID/SAN background. Thanks Luke
