This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
Hi Carissa, I'm finally getting back to you on your inquiry; sorry for the delay: re: > NCEP is starting the work on getting the new LDM boxes setup for the new > CONDUIT feeds. I am going through the tables and want to clean out any > old entries if possible. Can you peak at the lists below from the ldmd.conf > and let me know if you recognize anything outdated. > > # CONDUIT hosts > allow ANY ^conduit\.unidata\.ucar\.edu .* ^data2/TIGGE_resend > allow ANY ^conduit1\.unidata\.ucar\.edu .* ^data2/TIGGE_resend > allow ANY ^conduit2\.unidata\.ucar\.edu .* ^data2/TIGGE_resend > allow ANY ^conduit3\.unidata\.ucar\.edu .* ^data2/TIGGE_resend > allow ANY ^atm\.geo\.nsf\.gov .* ^data2/TIGGE_resend > allow ANY ^atm\.cise-nsf\.gov .* ^data2/TIGGE_resend > allow ANY ^f5\.aos\.wisc\.edu .* ^data2/TIGGE_resend > allow ANY ^idd\.aos\.wisc\.edu .* ^data2/TIGGE_resend > allow ANY ^flood\.atmos\.uiuc\.edu .* ^data2/TIGGE_resend > allow ANY ^(idd-ingest|iddrs3)\.meteo\.psu\.edu .* > # TIGGE hosts > # NCAR > ALLOW ANY ^dataportal\.ucar\.edu .* > ALLOW ANY ^datagrid\.ucar\.edu .* > # ECMWF > ALLOW ANY ^193\.61\.196\.74 .* > #TEST from ldmex > ALLOW ANY ^140\.90\.193\.99 .* > #TEST from node6 > ALLOW ANY ^192\.168\.0\.106 .* Question: - are there other ALLOWs in the ~ldm/etc/ldmd.conf file(s), or is this the complete list? As far as entries in your list that are archaic, the following entries can be removed as the machines or subnets no longer exist: allow ANY ^atm\.geo\.nsf\.gov .* ^data2/TIGGE_resend allow ANY ^f5\.aos\.wisc\.edu .* ^data2/TIGGE_resend The other ALLOW entries are valid, but the entry for Penn State should have the 'not' clause in its ALLOW: allow ANY ^(idd-ingest|iddrs3)\.meteo\.psu\.edu .* ^data2/TIGGE_resend Unless there are other ALLOWs that are not shown in the list above, the list (which includes some small changes that are useful) would be: # CONDUIT hosts ALLOW ANY ^conduit(|[0-9])\.unidata\.ucar\.edu\.?$ .* ^data2/TIGGE_resend ALLOW ANY ^atm\.cise-nsf\.gov\.?$ .* ^data2/TIGGE_resend ALLOW ANY ^idd\.aos\.wisc\.edu\.?$ .* ^data2/TIGGE_resend ALLOW ANY ^flood\.atmos\.uiuc\.edu\.?$ .* ^data2/TIGGE_resend ALLOW ANY ^(idd-ingest|iddrs3)\.meteo\.psu\.edu\.?$ .* ^data2/TIGGE_resend # TIGGE hosts # NCAR ALLOW ANY ^dataportal\.ucar\.edu\.?$ .* ALLOW ANY ^datagrid\.ucar\.edu\.?$ .* # ECMWF ALLOW ANY ^193\.61\.196\.74\.?$ .* # TEST from ldmex ALLOW ANY ^140\.90\.193\.99\.?$ .* # TEST from node6 ALLOW ANY ^192\.168\.0\.106\.?$ .* re: > Great. Next question. Currently the LDM queue is set at 6G for > operations. We have known that we need to up that threshold and have the > ability on these new systems to do that. But, since I am not planning on > taking LDM training until this fall :) could you provide some insight on > how to best optimize what that number should be. As far as the size of the queue is concerned, this is a great question that has no concrete answer, only guidelines. The best thing to do is to make the queue as large as possible while still being enough smaller than physical RAM so that the OS does not need to swap to disk. A good rule of thumb is to target the queue size to be big enough to hold at least 1 hour of data plus 20%. Even better, assuming that there is enough RAM, is to create a queue that holds 2 hours of data plus some buffer. Recent high water marks for CONDUIT volume is on the order of 5.3 GB/hr, but this seems to be lower than it has been in the past (I recall over 6 GB/hr). I think we need to plan for the volume to double in the not too distant future, so a volume of 10-12 GB/hr would not be unreasonable. Using the 2 hour target for queue residency time would result in a queue that is between 20-24 GB in size ** assuming ** that there is enough memory left over to run all routines without needing to swap to disk. Question: - how much RAM will the new machines have? If there is 30 GB, I would size make the queue 20 GB. We can go into other issues regarding LDM queue tuning when you attend the training workshop in the fall. 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: HGF-659268 Department: Support CONDUIT Priority: Normal Status: Closed