A queue is not needed for that,
its like buing tickets for a lottery, if every one buys the same amount the chance to win an upload slot is spread evenly, but if some buy more tickets than others, their chance to win is biased.
And thats what I will do for the upload priority, users requesting high priority files wil have a better chance to win in the upload slot lottery than clients requesting a normal file.
That should in the end appear simmilar to emule's release prioritys
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