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>From: Bill Fingerhut <address@hidden> >Organization: LSC >Keywords: 199905101610.KAA28438 X server software Hi Bill- >I don't know the source, but someone has suggested that we >make substantial changes to our metlab. A test is to be >conducted this week to convince us that the idea will work. >I hate to make a big decision on the sole basis of what I >can see. So, I am asking you to please advise me of any >information that I should also consider. > >The idea is to have each workstation run Windows NT; run all >Unidata applications on the server; use X server viewer >on each workstation. The drawbacks to this are sometimes not having enough colors on the NT workstations and the load on the server. Try using displays that have lots of colors. Especially make sure that all the GEMPAK applications will work in this mode. You also need a way of logging in from each workstation with a different account so there are not conflicts. You _CANNOT_ use the same account on all the workstation to run McIDAS. >The test is to display a McIDAS satellite loop on 10 work- >stations simultaeously, to see if the server can handle >the load. > >Do you know of any site that is configured this way? Plymouth State is set up in this way to do displays of McIDAS-X and WXP. I don't know if they are also using GEMPAK on their Win95 workstations. I also think Univesity of Arizona might be doing this as well. >Do you think it has merits? I think it is a tradeoff of one type of administration for another. You lose having to administer the Unix systems on the clients, but gain the X and Windows NT administration. Plus, Unix is a much more stable operating system than WindowsNT. Might see more "three fingered salutes" under NT. You are going to need a pretty powerful server to serve 10 workstations. It will need a lot of shared memory and physical memory. There will also be considerable network traffic. >Do you think there are any serious drawbacks or pitfalls? Other than the ones above, no. Also, we don't have easy ways of supporting this configuration if you run into problems. We don't use X-Server software. You might see a performance hit with the network traffic and disk activity on the server. >What should I ask, etc? Let the loops run for a long time and overlay data on top. Also, have all the systems start loading the loops at the same time and then load a different loop to see how things bog down. With McIDAS, the memory is preallocated when you start the session so there is no (or little) new memory needed after the session starts. With GARP, memory is allocated as needed, so the more frames you loop, the greater the load on the server. I would strongly advise you to try running GARP on all machines at the same time with long loops. Also, the X server will need to be run in 8-bit mode for GEMPAK and McIDAS to work correctly. We'd be interested in hearing the results of your test especially if it works. In particular, what are you using for a server and what X-Window software are you using. Don ************************************************************* Don Murray UCAR Unidata Program address@hidden P.O. Box 3000 (303) 497-8628 Boulder, CO 80307 ************************************************************* Unidata WWW Server http://www.unidata.ucar.edu/ McIDAS Demonstration Machine http://mcdemo.unidata.ucar.edu/ *************************************************************