conf - LAM node process schema
Most LAM/MPI used can disregard this page.
A process schema lists the system processes that will constitute the LAM
environment on a particular node. LAM developers will find process schemata
very useful for debugging and for generating custom systems.
Separate default configurations files are normally used for booting either the
single-daemon version (conf.lam) or the external-servers version (conf.otb).
The single-daemon version is used by default. The external-servers version is
typically used by LAM developers when debugging LAM services. The
-c
option to
hboot(1) specifies the file name of a custom process schema. This
capability is not available with
lamboot(1).
Application programs can be booted with the LAM environment by including the
program name in the process schema.
The process schema grammar defines three types of statements: comments,
processes, and options.
Comments begin with # and terminate with a newline.
Process statements consist of a filename, command line arguments, and possibly
options local to the process. The command line arguments are passed to the
process when it is started. The process options are used by the booting tools
before starting the process.
Filenames may include application programs and any of the system processes
listed below.
- bforward
- bufferd helper, forwards remote messages.
- bufferd
- creates, kills, sweeps, and states buffers.
- dli_inet
- sends data on network connections.
- dlo_inet
- receives data from network connections.
- echod
- echoes messages; can be used to test nodes and links.
- filed
- serves file access.
- flatd
- provides symbolic access to node memory.
- iod
- handles stdio data of processes.
- kenyad
- controls and monitors processes.
- kernel
- coordinates message passing.
- lamd
- single-daemon version of all servers excluding ledd and
mtvd.
- ledd
- controls LEDs.
- loadd
- loads executable files onto nodes.
- mtvd
- controls a pixel map display.
- router
- maintains routing tables.
- traced
- collects and transports trace data.
Processes are started in the order given in the process schema, and for LAM, the
order is important. The kernel must be first.
Process options are placed inside braces {} following the command line
arguments. Process options consist of a keyword followed by an assigned value
in parentheses. Options that are not explicitly given have default settings.
Options inside braces in process statements apply only to that process.
Options outside process statements apply to all processes that appear later in
the process schema, unless locally overridden. All the options are listed
below:
- inet_topo
- a string of dli_inet or lamd options, global only, default
null
- rtr_topo
- a string of router options, global only, default null
- delay
- waiting time in seconds after process boot, default 0
The inet_topo and rtr_topo options can be overridden from the command line of
hboot(1) using the -I and -R options respectively.
Following are example process schemata. The first file is used for an OTB node
in LAM.
##
## typical LAM process schemata
##
lamd $inet_topo
The second file is used by LAM developers to control each server as an
independent process, typically during debugging.
##
## external-servers LAM process schemata
##
##
## The kernel is listed first.
##
kernel $delay
##
## daemons
##
router
kenyad
dli_inet $inet_topo
dlo_inet
bufferd
bforward
loadd
echod
flatd
filed
traced
iod
- $LAMHOME/etc/lam-conf.lamd
- default LAM node process schema, where $LAMHOME is the
installation directory
- $LAMHOME/etc/lam-conf.separate
- example external-servers node process schema used when
debugging LAM
hboot(1)