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Hi Jack, > We are setting up a Linux Cluster dedicated to 3D Data Visualization and/or > powerpoint presentations:) > My question is the status of the cluster code, any examples? We are using > Redhat 7.3? Excellent question, which has motivated me to clean up the VisAD cluster work a bit and set up an example for you. The idea is that data are distributed across the nodes (i.e., processors) of a cluster, with one file per node. These are then visualized interactively on a user workstation. Cluster nodes are generally not visible (in the sense of Internet routes) from user workstations. Instead the nodes are visible from a cluster host and the host is visible from user workstations. So VisAD runs one Java command on each cluster node, one command on the cluster host, and one command on the user workstations. I haven't done anything yet with automatically launching the commands on the cluster nodes, but will be happy to work with you in setting that up after you try our example. Our example uses four files of output from the WRF model, that should be installed on four cluster nodes. The files are available from: ftp://ftp.ssec.wisc.edu/pub/visad-2.0/wrf_data/ and are named: wrfout_01_000000_0000 wrfout_01_000000_0001 wrfout_01_000000_0002 wrfout_01_000000_0003 You'll also need the latest untested VisAD from: ftp://ftp.ssec.wisc.edu/pub/visad-2.0/untested/visad.jar Note that the corresponding VisAD source is available from: ftp://ftp.ssec.wisc.edu/pub/visad-2.0/untested/visad_src-2.0.jar You'll need Java installed on all four cluster nodes, the cluster host and the user workstation. Install the data files on the four nodes and the new untested visad.jar on all machines. And make sure rmiregistry is running on all these machines too. Then run the following: On cluster node1: java -cp visad.jar visad.cluster.TestProxyCluster 1 wrfout_01_000000_0000 On cluster node2: java -cp visad.jar visad.cluster.TestProxyCluster 2 wrfout_01_000000_0001 On cluster node3: java -cp visad.jar visad.cluster.TestProxyCluster 3 wrfout_01_000000_0002 On cluster node4: java -cp visad.jar visad.cluster.TestProxyCluster 4 wrfout_01_000000_0003 Please ignore debug messages on cluster nodes, but . . . Wait for "data ready as ..." on all four cluster nodes. On cluster host: java -cp visad.jar visad.cluster.TestProxyCluster 0 node1 node2 node3 node4 Wait for "data ready as ..." on cluster host. On user workstation: rmiregistry & java -cp visad.jar visad.cluster.TestProxyCluster 5 host When 3-D window pops up, click on "Maps". When maps window pops up, click on "Detect" and "Done". After "please wait ..." message in 3-D window goes off, click on "Widgets". When widgets window pops up, slide "RRP" slider over to about 0.003. When iso-surfaces appear, click "Go" to animate. Note that 'node1', 'node2', 'node3' and 'node4' are the IP names of the four cluster nodes, visible from the cluster host. And 'host' is the IP name of the host. The demo is essentially a SpreadSheet cell, applied to a weather model output data set. It could be applied to other kinds of data, with a little effort. We used a SpreadSheet cell to test and demonstrate a wide range of VisAD interaction modes with cluster data. You will undoubtedly encounter problems. Please let me know and we'll solve them together. I would be very happy to have someone interested in working with this VisAD cluster code. Cheers, Bill ---------------------------------------------------------- Bill Hibbard, SSEC, 1225 W. Dayton St., Madison, WI 53706 hibbard@xxxxxxxxxxxxxxxxx 608-263-4427 fax: 608-263-6738 http://www.ssec.wisc.edu/~billh/vis.html
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