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I guess if the data comes in faster, then it's a fair trade off. -----Original Message----- From: address@hidden To: Robert Mullenax Cc: 'Mike Leuthold '; 'address@hidden '; address@hidden Sent: 1/10/2005 3:13 PM Subject: Re: problem with CONDUIT ETA/GFS since 4 Jan 2005 All, Apparently these emails were not distributed to the entire conduit list. Here's what's going on. In a Jan 5 email from Steve Chiswell to Jerry, Me and support-conduit: >Jerry, > >Yesterday at 1830Z we implemented a parallel queueing scheme at the >NWS that we hope will improve the timeliness of data being ingected into >the CONDUIT data stream. Any feedback you can provide on how >this affects your reception would be greatly appreciated. > >Since data will be inserted in parallel, you will notice that multiple >model runds and forecast times will probably be interspersed where >previously they had been serialized. > >I watched the 00Z GFS last night, and the posting gap between f084 and >f132 was matched on the FTP server at 0422Z and later at 0509Z, the >other grids were posted to the NWS servers, so all appears to be >behaving correctly on this end. > >Steve Chiswell >Unidata User Support > An email from Me to Steve last Friday (Jan 7) > Steve, > > Since the parallel queueing scheme was implemented, I have noticed two > things, both are problematic. > > 1) The lag goes way up since so much more data is being inserted into > the queue in a shorter amount of time. I was getting lag times of 3000-4000 > seconds in peak gfs times. I moved my ldm queue on f5 to a faster disk, and > that helped, but it's still getting up to 300-400 seconds. > > 2) The biggest problem I see, is that now it takes MUCH longer for the > early hours of a forecast run to complete. Most of my model plotting > scripts and all of our real-time mesoscale modelling efforts here > take advantage of the fact that an entire model run doesn't need to be > complete before we can start. Since the parallel queueing was enabled, > the 00 hour forecast of the eta model for example, takes over an hour > to get here, where previously it was taking maybe 5 minutes. > > If this is how it's going to be, I'd much prefer the old serial ingest, > or maybe some kind of blend, so the first 12 hours or so (or 48 or > whatever) of a model run can get priority. > > It really hurts us to have the 00 hour forecast complete around the > same time as the later forecasts, even if the entire model run gets > in faster as a result. > > For what it's worth. > > Pete > Steve's reply on Friday [again to me, Jerry and support-conduit] >Pete, > >In pushing the queing lag time from the NWS computer queueing the data >to the NWS computer doing the data insertion, some of the latency is >now in the LDM queue as the volume you are receiving is increased >into a shorted time window- whereas before it was all in the insertion. > >I agree that the parallel insertion is at some expense of the early >files since the slug of insertion starts slowing that down and >we'll have to see if we can optimize the insertion. > >Steve Chiswell >Unidata User Support FYI. Pete In a previous message to me, you wrote: > Yes. We see the same problem. > >-----Original Message----- >From: address@hidden >To: address@hidden >Sent: 1/10/2005 2:41 PM >Subject: problem with CONDUIT ETA/GFS since 4 Jan 2005 > >Hello, > As of 4 Jan 2005, I've noticed that the model products are being >sent out in a mixed up time sequence. Previously, all the F000 fields >were sent, then F003, and so on. Now, the times are all mixed up with >F000 fields still coming in even though the F072 fields have just >started. >In the past, by T+2.5 hours, the ETA212 was up to having at least F048 >finished, thus I was able to start a local WRF run. Now, I have to wait >much longer for F048 to complete, delaying substantially the start of my >real time WRF runs. Is any one else seeing this sort of problem? > >Thanks. >Mike > > >Below is sample: > >Jan 10 20:32:47 pqutil: 23958 20050110203228.114 CONDUIT 078 >/afs/.nwstg.nws.noaa.gov/ftp/SL.us008001/ST.opnl/MT.nam_CY.18/RD.200501 1 >0/PT.grid_DF.gr1/fh.0060_tl.press_gr.awip3d >!grib/ncep/ETA_84/#212/200501101800/F060/VVEL/350_mb! 000078 >Jan 10 20:32:48 pqutil: 23958 20050110203243.766 CONDUIT 169 >/afs/.nwstg.nws.noaa.gov/ftp/SL.us008001/ST.opnl/MT.nam_CY.18/RD.200501 1 >0/PT.grid_DF.gr1/fh.0045_tl.press_gr.awip3d >!grib/ncep/ETA_84/#212/200501101800/F045/TMP/225_mb! 000169 >Jan 10 20:32:48 pqutil: 26942 20050110203239.440 CONDUIT 300 >/afs/.nwstg.nws.noaa.gov/ftp/SL.us008001/ST.opnl/MT.nam_CY.18/RD.200501 1 >0/PT.grid_DF.gr1/fh.0024_tl.press_gr.awip3d >!grib/ncep/ETA_84/#212/200501101800/F024/SPFH/575_mb! 000300 > > >-- >Mike Leuthold >Atmospheric Sciences/Institute of Atmospheric Physics >University of Arizona >address@hidden >520-621-2863 > >"Is there some difference between the despotism of the monarch and > the despotism of the multitude?" > >Edmund Burke -- +>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+ ^ Pete Pokrandt V 1447 AOSS Bldg 1225 W Dayton St^ ^ Systems Programmer V Madison, WI 53706 ^ ^ V address@hidden ^ ^ Dept of Atmos & Oceanic Sciences V (608) 262-3086 (Phone/voicemail) ^ ^ University of Wisconsin-Madison V 262-0166 (Fax) ^ <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+