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>From: Russ Dengel <address@hidden> >Organization: SSEC >Keywords: 200106191811.f5JIB0110437 McIDAS-X NEXRAD server Russ, > I just found an "interesting" problem in the nexrad server when >doing a ID=LIST. Operations here at SSEC has set the number of products >per ID to 250. When we issue the command: > > IMGLIST NEXRAD/BREF1 ID=LIST > >We usually get a server timeout failure from the NEXRAD server. I assume >that is because the machine is too slow to wade throught 250 products >for ~150 stations. The timeout is 2 minutes and on a rare occasion, the >server does complete before the 2 minutes expires. This was a common problem before I did one of my rewrites of my server, but should be fixed now IF one files the data in a logical manner AND then informs the server of the filing's use of the stations' IDs in the hierarchy. I would venture to guess that the problem on your system lies in how the products are being filed or in how the access to the products has been defined. I say this because we save a full day's worth of data for each station for each product on motherlode.ucar.edu This means that for a full day there can be up to 288 files for each station, and the time to get a list of stations back from motherlode typically is in the one to several seconds range. If one does not setup the filing to be in a logical hierarchy, or if one doesn't define the dataset access to explicitly tell the server that the station ID is part of the hierarchy and/or name, then the server has to open each file to find out what station the file represents. This would fit your observation that a timeout occurs when trying to open, read to extract ID information, and then sort 150*250 files. So, the first place to look is in how the files are being saved. The second is in how the dataset is defined. BTW, I _did_ find a bug in the listing of available stations when all of the files and product types are put into a single directory (i.e., no hierarchy). This problem results in a failure to list the available stations, not in the slowness of listing them. I will be updating the CVS repository with my fix for this as soon as I get a chance to pretty up some other code that irks me right at the moment. Tom -- +-----------------------------------------------------------------------------+ * Tom Yoksas UCAR Unidata Program * * (303) 497-8642 (last resort) P.O. Box 3000 * * address@hidden Boulder, CO 80307 * * Unidata WWW Service http://www.unidata.ucar.edu/* +-----------------------------------------------------------------------------+