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Hi David, Did you try changing your 5-way split CONDUIT feed requests to 10 as Pete had suggested? I ask because we have seen a marked improvement in CONDUIT receipt latencies being reported by freshair2: http://rtstats.unidata.ucar.edu/cgi-bin/rtstats/iddstats_nc?CONDUIT+freshair2.atmos.washington.edu We also had occasion to look at the receipt latencies for the NEXRAD2 feed on both freshair1 and freshair2: freshair1: http://rtstats.unidata.ucar.edu/cgi-bin/rtstats/iddstats_nc?NEXRAD2+freshair1.atmos.washington.edu freshair2: http://rtstats.unidata.ucar.edu/cgi-bin/rtstats/iddstats_nc?NEXRAD2+freshair2.atmos.washington.edu As you can see from comparing these plots, latencies being reported by freshair1 are significantly less than what is being reported by freshair2. This is the same as for the CONDUIT feed. The questions that come to mind are: - what is the difference between the network connections to freshair1 and freshair2? This brings up a couple of questions: - is freshair2 using a Gbps Ethernet interface for LDM ingestion? - if yes, is the interface actually running at Gbps speed? The easiest way to test this is as follows: <as 'root'> ethtool <ethernet interface> We have seen instances where Gbps Ethernet interfaces were actually running at 100 Mbps speeds, and/or it was not running full Duplex, and either of these was greatly impeding the flow of data into the machine. - how can the latencies on freshair2 be lessened/minimized/mitigated? Aside from optimizing some kernel settings related to networking, the most straightforward way to mitigate this is to split feed REQUESTs. This may help the situation on freshair2 since we see that it is requesting all of NEXRAD2 using a single LDM configuration refile REQUEST. I recommend: change: request NEXRAD2 ".*" idd.unidata.ucar.edu to: request NEXRAD2 "[02468]/[IES]" idd.unidata.ucar.edu request NEXRAD2 "[13579]/[IES]" idd.unidata.ucar.edu And then stop and restart your LDM. Aside: When looking through the LDM log file on the real server back end machine of our IDD relay cluster idd.unidata.ucar.edu that is feeding freshair2, I saw that you are now using a 10-way split REQUEST for CONDUIT, so my first question above has been answered. Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: VXV-940104 Department: Support CONDUIT Priority: Normal Status: Closed =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.