Improve the CLI manual quick recipe for launching a compute engine.
@@ -214,7 +214,7 @@ name.
OpenDatabase("thunder:/usr/local/visit/data/wave.visit", 17)
Opening a compute engine
-~~~~~~~~~~~~~~~~~~~~~~~~
+------------------------
Sometimes it is advantageous to open a compute engine before opening a
database. When you tell VisIt to open a database using the OpenDatabase
@@ -231,9 +231,57 @@ launch the engine such as the number of processors.
::
- # Open a remote, parallel compute engine before opening a database
- OpenComputeEngine("mcr", ("-np", "4", "-nn", "2"))
- OpenDatabase("mcr:/usr/local/visit/data/multi_ucd3d.silo")
+ # Open a local, parallel compute engine before opening a database
+ # Use 4 processors on 2 nodes
+ OpenComputeEngine("localhost", ("-np", "4", "-nn", "2"))
+ OpenDatabase("/usr/local/visit/data/multi_ucd3d.silo")
+
+The options for starting the compute engine are the same as the ones used
+on the command line. Here are the most common options for launching a
+compute engine.
+
+::
+
+ -l <method> Launch in parallel using the given method.
+ -np <# procs> The number of processors to use.
+ -nn <# nodes> The number of nodes to allocate.
+ -p <part> Partition to run in.
+ -b <bank> Bank from which to draw resources.
+ -t <time> Maximum job run time.
+ -machinefile <file> Machine file.
+
+
+The full list of parallel launch options can be obtained by typing
+``visit --fullhelp``. Here is a more complex example of launching a compute
+engine.
+
+::
+
+ # Use the "srun" job launcher, the "batch" partition, the "mybank" bank,
+ # 72 processors on 2 nodes and a time limit of 1 hour
+ OpenComputeEngine("localhost",("-l", "srun",
+ "-p", "batch",
+ "-b", "mybank",
+ "-np", "72",
+ "-nn", "2",
+ "-t", "1:00:00"))
+
+You can also launch a compute engine using one of the existing host
+profiles defined for your system. In this particular case we know that
+the third profile is for the "parallel batch pbatch" profile. If you
+didn't know this you could print "p" to get all the properties.
+
+::
+
+ # Set the user name to "user1" and use the third profile,
+ # overriding a few of its properties
+ p = GetMachineProfile("quartz.llnl.gov")
+ p.userName="user1"
+ p.activeProfile = 2
+ p.GetLaunchProfiles(2).numProcessors = 72
+ p.GetLaunchProfiles(2).numNodes = 2
+ p.GetLaunchProfiles(2).timeLimit = "00:30:00"
+ OpenComputeEngine(p)
Working with plots
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