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Hi Deb, re: > Hey thanks for the prompt response. No worries. I apologize for not being able to get back to your inquiry yesterday, some other things came up that consumed the afternoon. re: > I think I am not speaking LDM well. No worries. re: > When you refer to "full GRIB2 message", I'm assuming that a full GRIB2 > message is: > > Jun 11 21:49:46 pqutil INFO: 42796 20180611214930.210 CONDUIT 320 > data/nccf/com/gfs/prod/gfs.2018061118/gfs.t18z.pgrb2.1p00.f057 > !grib2/ncep/GFS/#000/201806111800F057/PRES/0 - CCBL! 00 > 0320 Yes. The process running at NCEP (the source of the CONDUIT feed) carves up the output from the model into individual GRIB2 messages and inserts those into an LDM queue and then they are distributed to toplevel IDD relays for further distribution to end-users. re: > Our ingest (with the appropriate tabs of course) > CONDUIT > ^data/nccf/com/gfs/prod/gfs.([12][0-9])([0-9][0-9])([01][0-9])([0-3][0-9])([0-2][0-9])/(gfs.*pgrb2.1p00.)f([0-9]*[02468]) > !(.*)! > FILE -close -log > /data/gfs/gfs1.00deg/test/\1\2\3\4/gfs.\1\2\3\4\5.pgrb2.1p00.f\7 > > stores all 1p00.f057 messages into a single file called > gfs.2018061118.pgrb2.1p00.f057 which many others use. OK. This is the first time that you mentioned that the objective was to store all of the GRIB2 messages for a model output time step in a single file. Your inquiry makes a lot more sense to me now! :-) re: > Currently, those users have scripts that run at a time when it is assumed > that all of the data for 18Z 1p00 f057 has been written to > gfs.2018061118.pgrb2.1p00.f057. > > Obviously that assumption causes alot of reprocessing when data are missed > for some reason. Or, when the script is run before the full set of GRIB2 messages from the time step have been received. re: > So they asked if I could streamline that process to run > their scripts via LDM EXEC once the entire > gfs.2018061118.pgrb2.1p00.f057 ingest > is complete. And from my understanding, the answer is no. The answer is actually yes and no, but the yes option will require more complexity in your LDM processing. You are correct in thinking that there is no apriori way to tell if all of the GRIB2 messages have been received ** UNLESS ** you have a list of all of the GRIB2 messages that were part of the original output of the model. Luckily, this is possible with CONDUIT (but not for GRIB2 messages received in the NGRID feed that originates from a NOAAPort downlink) since a manifest file (a file that has a listing of all GRIB2 messages that were successfully inserted into the originating LDM queue) is sent right after the last GRIB2 message is inserted into the originating LDM queue. This means that you should be able to: - use the arrival of the manifest file as an indication that the great majority of GRIB2 messages have been received Why not as an indication that all GRIB2 messages have been received? The reason is that since the route that each LDM products (GRIB2 messages in this case) goes through before arriving at your LDM is not fixed, so the products can be received in an order that is different from the order of insertion into the originating LDM's queue, and this, in turn means that you could receive the manifest file before the last GRIB2 message(s) are received. The difference in time between the receipt(s), however should be "small", so you could setup an action for the receipt of the manifest that then waits for some time (exactly how much is hard to say, but a couple/few minutes should be sufficient) before kicking off the end-user processing OR sends a notification that end-user processing can run. - compare an inventory of GRIB2 messages received against the list in the manifest file This would allow you to _know_ if you received all of the products (GRIB2 messages) that were made available via inserts into the LDM queue at the originating site. re: > Hope that makes some sense. Yes, it makes good sense to me now. OK, so your next question is undoubtedly what the Product IDs for the manifest files look like? The thing you need to know about the manifest files is what their Product IDs look like since it is the Product IDs that you must create extended regular expressions to match and use in pattern-action file actions. The key piece here is that the word 'status' (no quotes) is included in the Product ID for each manifest file. To see what the manifest files you are receiving in your CONDUIT feed, run the following: <as 'ldm' on your machine that is receiving the CONDUIT feed> notifyme -vl- -f CONDUIT -p status -o 10000000 Example output: ... 20180614T160025.877556Z notifyme[1902] INFO notifyme.c:222:notifymeprog_5() 60300 20180614155943.449779 CONDUIT 417 .status.data/nccf/com/gfs/prod/gfs.2018061412/gfs.t12z.pgrb2.0p50.f087 000417 20180614T160026.941924Z notifyme[1902] INFO notifyme.c:222:notifymeprog_5() 60303 20180614155943.503915 CONDUIT 417 .status.data/nccf/com/gfs/prod/gfs.2018061412/gfs.t12z.pgrb2.0p25.f090 000417 ... The Product IDs in this listing snippit are: .status.data/nccf/com/gfs/prod/gfs.2018061412/gfs.t12z.pgrb2.0p25.f090 000417 .status.data/nccf/com/gfs/prod/gfs.2018061412/gfs.t12z.pgrb2.0p50.f087 00041 Comment: - the LDM 'notifyme' utility is, in my opinion, THE most useful LDM command for end users It not only can be used to show you what you are receiving/have received, it can be used to show you what your upstream feed host is receiving/has received. It can also be used to test extended regular expressions that you may want to use in the LDM configuration file (~ldm/ldmd.conf) REQUEST lines and in pattern-action file actions. So, your job (if you choose to accept it Mission Impossible ;-) is to: - figure out which manifest files you want to use in your processing - write a pattern action file action that does something with the manifest file(s) that you are interested in For example: compare what was received for the model output time step with what was inserted into the LDM queue at NCEP; send notifications to users that the data is ready for processing; etc. One last comment in clarification of something I said above: The CONDUIT feed is the only feed that contains a manifest file, and this is possible since the process that is creating LDM products from model output (i.e., carving up the large model output file into individual GRIB2 messages) is also creating the manifest files. This is not possible for feeds that originate from NOAAPort since we have no way of knowing what the list of products actually sent in the SBM is. I hope that this all makes sense. If it doesn't, please let us know! 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: JXK-104385 Department: Support LDM 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.