Brice, > We are running 6.11.6. Good. > I think I understand your answer about latency and queue size, but I have a > question about implementation. If the upstream feeders are running only > small amounts of data through their queue, i.e. not full NOAAPort for > instance just some specific local implementation, how am I going to know how > to balance the size? I'm not sure what you're asking. The upstream LDM-s will need a queue size that ensures that none of their data-products resides in their queue longer than their LDM's maximum latency setting -- so that they (the upstream LDM-s) can reject incoming duplicates. If the upstream LDM-s don't make any REQUEST-s for data-products, then their queues can be as small as the amount of time that they could be offline. Our NOAAPORT ingest LDM-s are in this latter category and their queues can typically guarantee only the last 15 minutes of data. (We run redundant NOAAPORT ingest LDM-s, so we don't care if their queues are small.) If, instead, your talking about the size of the downstream LDM's queue, then it needs to be large enough so that the minimum residence time of a data-product in the queue is greater than the maximum latency parameter of that LDM (which is one hour by default). This needs to be the case regardless of the number or configuration of the downstream LDM's REQUEST entries. > And, could the LDM settings and checks you propose handle that sort of > asymmetry? Asymmetry of feeds is irrelevant: the only things that matter are the minimum residence time in the queue (regardless of feed) and the maximum latency parameter. If the former is greater than the latter, then duplicates (regardless of feed) will always be rejected. > Thanks, > > Brice Regards, Steve Emmerson Ticket Details =================== Ticket ID: VTV-967500 Department: Support LDM Priority: Normal Status: Closed
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