NAME
lamnodes - Resolve LAM node/CPU notation to Unix
hostnames.
SYNTAX
lamnodes [-chin] [<where>]
OPTIONS
- -c
- Suppress printing the CPU count for each node.
- -h
- Print the command help menu.
- -i
- Print IP addresses (instead of IP names)
- -n
- Suppress printing CPU count for each node
DESCRIPTION
The lamnodes command is used to resolve
LAM node/CPU nomenclature to Unix hostnames. It can be used to
determine the current running configuration of the LAM/MPI run-time
environment, and generate a boot schema that can be used to launch
LAM in the future.
By default, lamnodes will print out the node number,
default IP name, CPU count, and per-node flags for each node in the
running LAM. gethostbyaddr(3)
is used to obtain default hostnames. If gethostbyaddr(3)
fails, the IP number is displayed instead.
This command can be used by setup shell scripts (and the like)
to determine information from a currently-running LAM universe. For
example, use lamnodes to resolve particular CPUs and/or nodes to
specific unix hostnames. In a batch environment, lamnodes
can be used to determine which CPUs share a common node (note that
MPI_GET_PROCESSOR_NAME can be used for a similar effect in an MPI
program).
lamnodes also shows per-node flags. Currently defined
flags are:
- origin
- The node where lamboot was executed.
- this_node
- The node where lamnodes is running.
- no_schedule
- The node will not be used to run MPI and serial processes when
N and C are used to mpirun and lamexec.
EXAMPLES
- lamnodes N -n
- Display IP names and CPU counts for all nodes. This output can
be saved and later used with lamboot(1).
- lamnodes C -n -c
- Display the IP name of the nodes containing each CPU, and
suppress the LAM node number and CPU count. This output can be
saved and later used with lamboot(1).
SEE ALSO
bhost(5),
gethostbyaddr(3),
lamboot(1)