PVMD {rpvm} | R Documentation |
Start new pvm daemon, add or delete hosts and stop pvmd.
.PVM.start.pvmd (hosts = "", block = T) .PVM.addhosts (hosts) .PVM.delhosts (hosts) .PVM.halt ()
hosts |
a character vector, arguments to pvmd |
block |
logical, if true, block until startup of all hosts complete |
.PVM.start.pvmd
starts a pvmd3 process, the master of a
new virtual machine. It returns as soon as the pvmd is started and
ready for work. If the block
parameter is nonzero and a
hostfile is passed to the pvmd as a parameter, it returns when all
hosts marked to start have been added.
.PVM.addhosts
takes a vector of host names and add them to the
virtual machine. The names should have the same syntax as lines of a
pvmd hostfile (see man page for pvmd3): A hostname followed by options
of the form xx=y.
The status of hosts can be requested by the application using
.PVM.mstats
and .PVM.config
. If a host
fails it will be automatically deleted from the configuration. Using
.PVM.addhosts
a replacement host can be added by the
application, however it is the responsibility of the application
developer to make his application tolerant of host failure. Another
use of this feature would be to add more hosts as they become
available, for example on a weekend, or if the application dynamically
determines it could use more computational power.
.PVM.delhosts
deletes the computers pointed to in hosts
from the existing configuration of computers making up the virtual
machine. All PVM processes and the pvmd running on these computers
are killed as the computer is deleted.
If a host fails, the PVM system will continue to function and will
automatically delete this host from the virtual machine. An
application can be notified of a host failure by calling
.PVM.notify
. It is still the responsibility of the
application developer to make his application tolerant of host
failure.
.PVM.halt
shuts down the the entire PVM system including remote
tasks, remote pvmds, the local tasks (including the calling task) and
the local pvmd. Note, when I did this, it also kills the current R
session.
.PVM.start.pvmd
will return the result from .PVM.config
.
.PVM.halt
returns TRUE
if successful.
.PVM.addhosts
returns a vector of host ids that has been
successfully added to the virtual machine.
.PVM.delhosts
returns a vector of status codes for each
hosts successfulled removed from the virtual machine.
Na (Michael) Li nali@umn.edu and A.J. Rossini rossini@u.washington.edu
PVM documentation
# start a new virtual machine on local machine ## Not run: .PVM.start.pvmd () # add two more hosts to it .PVM.addhosts ("sparky", "thud.cs.utk.edu ep=$R_LIBS/rpvm/") # do some work ... # finished with one machine .PVM.delhosts ("thud.cs.utk.edu") # do some other work ... # finished with pvm .PVM.halt () ## End(Not run)