Running without VTserver

Instead of starting VTserver as rank #0 with the contact strings of all application processes, one application process can take over that role. It becomes rank #0 and calls VT_serverinit() with the information normally given to VTserver. This changes the application startup only slightly.

A more fundamental change is supported by first starting one process with rank #0 as server, then taking its contact string and passing it to the other processes. These processes then give this string as the initial value of the contact parameter in VT_clientinit(). To distinguish this kind of startup from the dynamic spawning of process described in the next section, the prefix S needs to be added by the application before calling VT_clientinit(). An example where this kind of startup is useful is a process which preforks several child processes to do some work.

In both cases it may be useful to note that the command line arguments previously passed to VTserver can be given in the argc/argv array as described in the documentation of VT_initialize().

For more complete information about compiler optimizations, see our Optimization Notice.