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Chiz, > > There are some things we can do to tune the LDM requests, > and we can look at other upstreams. > > There is currently 1 bottle neck that drives the initial latencies up. > This is the T-1 line from NCEP to GSFC which is roughly capable of > delivering 550MB per hour. Since the AVN (now out to 84 hours) can exceed > 600MB, and the MRF is also pushing 500MB then things can get backlogged- > especially when NCEP has Cray crashes and then come back up and post > the data all at once. Not much we can do about that one (at least for now). > > I have found I can get better throughput to the upstream using > seaparte request lines like: > > request NMC2 ".*[036]$" 128.183.252.98 > request NMC2 ".*[147]$" nora.gsfc.nasa.gov > request NMC2 ".*[^013467]$" conduit_a I'll try that. I'll have to figure out the best way to do it though. Right now my request reads: request NMC2 "(.status)|(.*erl/icwf)|(.*mrf/(mrf|ens))|(.*ens/ens.*/tar)" flood. atmos.uiuc.edu which I *believe* should get me only status messages, eta, mrf and ensemble forecasts. (I don't really need the other stuff right now, so, since I don't have a downstream node for the NMC2 feed I restricted what I requested in an attempt to get better throughput) I guess I would just put two entries: request NMC2 "(.status)|(.*erl/icwf)|(.*mrf/(mrf|ens))|(.*ens/ens.*/tar).*[02468]$" flood.atmos.uiuc.edu request NMC2 "(.status)|(.*erl/icwf)|(.*mrf/(mrf|ens))|(.*ens/ens.*/tar).*[13579]$" 128.174.80.47 Or, actually, maybe these should read ??? : request NMC2 "(.status.*[02468]$)|(.*erl/icwf.*[02468]$)|(.*mrf/(mrf|ens).*[02468]$)|(.*ens/ens.*/tar.*[02468]$)" flood.atmos.uiuc.edu request NMC2 "(.status.*[13579])|(.*erl/icwf.*[13579])|(.*mrf/(mrf|ens).*[13579])|(.*ens/ens.*/tar.*[13579])" 128.174.80.47 I've used this trick in the past to split up the Unidata feed into FOS and MCIDAS. > > I provided an alias in our hosts table for the third entry above. > By using different names, the LDM actually will create a seperate > rpc.ldmd connection for each subset. > > The idea here is that all the conduit products have a sequence number > tagged on to the end, and the split requests seem to get more > round robin time from the router than a single request. > > Unfortunately PSU did not feel like they had a good connection to gsfc, > so the feed from back here same as UIUC, but I was wondering what your > traceroutes to profhorn.meteor.wisc.edu and nora.gsfc.nasa.gov look like. traceroute to wisc is OK, but not great: traceroute to profhorn.meteor.wisc.edu (144.92.131.143), 30 hops max, 40 byte packets 1 be102 (169.226.4.1) 4 ms 1 ms 1 ms 2 169.226.13.1 (169.226.13.1) 1 ms 4 ms 1 ms 3 at-gw3-alb-1-0-T3.appliedtheory.net (169.130.23.5) 2 ms 2 ms 2 ms 4 at-gw2-alb-0-0.appliedtheory.net (169.130.20.2) 3 ms 3 ms 3 ms 5 at-gw2-syr-1-1-0-T3.appliedtheory.net (169.130.1.22) 5 ms 5 ms 5 ms 6 at-bb1-pen-5-0-0-T3.appliedtheory.net (169.130.1.121) 42 ms 39 ms 39 ms 7 sl-bb10-pen-4-2.sprintlink.net (144.232.5.109) 62 ms 33 ms 48 ms 8 sl-bb10-nyc-6-0-622M.sprintlink.net (144.232.9.101) 37 ms 27 ms 34 ms 9 sl-bb10-chi-6-0.sprintlink.net (144.232.9.150) 37 ms 40 ms 37 ms 10 sl-gw14-chi-8-0-0.sprintlink.net (144.232.0.194) 287 ms 300 ms 275 ms 11 sl-napnet-2-0-0-T3.sprintlink.net (144.228.159.18) 43 ms 42 ms 44 ms 12 chi1-oc3.wisc.edu (207.227.0.202) 45 ms 52 ms 56 ms 13 r-peer-a4-0-0-3.net.wisc.edu (216.56.1.18) 47 ms * 75 ms 14 r-macc.net.wisc.edu (144.92.128.129) 70 ms 83 ms 87 ms 15 ProfHorn.meteor.wisc.edu (144.92.131.143) 120 ms 81 ms 75 ms This seems to be about typical. However, a tracroute to nasa looks really good! traceroute to nora.gsfc.nasa.gov (128.183.104.227), 30 hops max, 40 byte packets 1 be102 (169.226.4.1) 6 ms 1 ms 1 ms 2 169.226.13.1 (169.226.13.1) 1 ms 1 ms 1 ms 3 at-gw3-alb-1-0-T3.appliedtheory.net (169.130.23.5) 30 ms 2 ms 161 ms 4 at-gw2-alb-0-0.appliedtheory.net (169.130.20.2) 3 ms 4 ms 3 ms 5 at-gw2-syr-1-1-0-T3.appliedtheory.net (169.130.1.22) 6 ms 5 ms 5 ms 6 at-bb1-pen-5-0-0-T3.appliedtheory.net (169.130.1.121) 37 ms 16 ms 37 ms 7 128.161.250.1 (128.161.250.1) 29 ms 24 ms 26 ms 8 128.161.10.37 (128.161.10.37) 23 ms 20 ms 20 ms 9 rtr-wan1-ef.gsfc.nasa.gov (192.43.240.33) 25 ms 22 ms 25 ms 10 rtr-cbr5a-a.gsfc.nasa.gov (198.119.59.4) 21 ms 25 ms 21 ms 11 nora.gsfc.nasa.gov (128.183.104.227) 23 ms 24 ms 29 ms again these numbers are consistant for several tries. > > For the past month we have also been downgraded from out 100baseT > connection to a 10baseT connection while our building is rewired. > When our switch gets moved to the new wiring closet it could improve > things as well. > > > Steve Chiswell > Unidata User Support Thanks David David Knight Department of Earth and Atmospheric Sciences Tel: (518)-442-4204 SUNYA ES-228 Fax: (518)-442-4494 Albany, NY 12222 Email: address@hidden