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Niles, > I have a question about ldm configuration. > > Say we are ingesting level two nexrad radar data for the > Washington DC radar, KLWX. > > What we currently do is to have our request include all > radars in ldmd.conf : > > request NEXRD2 ".*" rasp.rap.ucar.edu > > And then only process KLWX in the pqact.conf : > > NEXRD2 > ^L2-(.*)/(KLWX)/([0-9][0-9][0-9][0-9][0-1][0-9][0-3][0-9])([0-2][0-9][0-5][0-9][0-5][0-9])/(.*)/(.*) > FILE /home/ldm/data/radar/\2/\3/\4_\6.\1 > > We're realizing that what that probably does is make for a much bigger > product queue, > which we'd like to avoid. So instead of doing that, we'd like to request only > that radar > in the ldmd.conf file : > > request NEXRD2 "KLWX" rasp.rap.ucar.edu > > and then leave the pqact.conf file open to any incoming radars : > > NEXRD2 > ^L2-(.*)/(.*)/([0-9][0-9][0-9][0-9][0-1][0-9][0-3][0-9])([0-2][0-9][0-5][0-9][0-5][0-9])/(.*)/(.*) > FILE /home/ldm/data/radar/\2/\3/\4_\6.\1 > > That way if we do add another radar we only have to edit ldmd.conf and not > pqact.conf. > > My question is - is this a good thing to do, Requesting only the data that you want will reduce bandwidth demand, upstream CPU usage, downstream CPU usage, and product -queue size -- all very good things! > will it have any effects > that we have not thought of. You will not be able to relay any data products that you have not requested. > I'm guessing load on the upstream host, rasp, might go > up slightly because it has to do more sorting, I think the CPU usage will actually be less. > but that network traffic would drop and > product queue size would drop significantly (the desired result for us). Without question. > So - is this a good move to make? Absolutely! Providing you're not interested in relaying the data that you're not receiving. > Niles. > > -- > > Work (USA) 303 497 2808 email address@hidden > Home (USA) 720 938 7332 email address@hidden (simple short text, receive > only) Regards, Steve Emmerson Ticket Details =================== Ticket ID: KIO-429794 Department: Support LDM Priority: Normal Status: Closed