SCore User Manual
a.out [-score option_string] arg1 arg2 ... argn
Here let us assume a.out is an executable file linked with
SCore-S library. During the initialization of SCore-S, the command
arguments are scanned, and SCore-S assumes that the argument following the
keyword -score is an SCore option string. The rest of the
arguments are passed to the user program,
a.out can run standalone on a hostmachine when requiring one
node. It should be invoked on a host that is an element host of a
workstation cluster when requiring more than one host. However, when
SCore-D is running on a workstation cluster, users can invoke their
programs on the host anywhere IP reachable to the cluster, if the host
machine and the cluster hosts are the same machine type.
If the user program is running with SCore-S library (standalone), the
program execution can be aborted by sending
(^C)to the invoked process. During the spawning
SIGINT is blocked, because SCore-S may fail to
spawn processes on the remote hosts. In the case of some cluster
hosts is down, the signal blocking is released when there is no answer
from the spawned process for more than 10 seconds. Sending
in this situation, spawned process keeps running. It is the user's
responsibility to kill the singleton process. Under SCore-D,
SIGINT to kill and
SIGTSTP to suspend are
Options in the option string is separated by commas (,) or blanks. When
each option is separated by blanks, the entire option string must be
quoted. The -score keyword and the following option string can be
placed anywhere in the command arguments. Each option setting
consists of keyword and value. Like shell environment
variables, the keyword and associated value are separated by an equals
(=) symbol character.
The option string is searched from left to right. If there are two or more
options having the same keyword, the leftmost one is taken. After
searching the option string, SCore tries to get the other option
string from shell environment variable named SCORE_OPTIONS.
If the user program is to run under SCore-D, the value of shell
environment variable named SCORED_OPTIONS is also taken as an
additional option string.
Effective options can vary depending on which library is linked with
the executable file. In general, the communication library and language
runtime library are required to be linked. Such libraries may have
different options from the others. Thus, the options listed in this
section is a minimum set.
SCore takes the value of shell environment variable
environ as a option string. Its format is the same as
the one in command argument. The option string spcified in the
environment variable can contain the default
This option setting is replaced by the environment variable
name and its value. SCore does not pass environment
variables of invoked the process to the processes spawned.
The program prints option setting information, and then exits.
The program first prints the current option setting, and then
starts its execution.
The pathname is a filename assumed to contain the cluster
configuration. Default is score.conf.
The number of host nodes required to run the program is
specified by number_of_nodes option. Note that the
specified number is taken as a request, and the actual number
of allocated hosts may be different.
The hostname is assumed to be SCore-D server host, and
SCore-S tries to connect to the host to submit a job.
The following two options are dedicated for the cluster having
Myrinet network interface.
The pathname is assumed to be a MCP filename. MCP
stands for Myrinet Control Program, and is the firmware for
Myrinet LANai processor that controls Myrinet interface.
In case the workstation cluster has two or more Myrinet
interfaces, this option specifies which interface is to be
used. The default unit number is 0.
If the debug
option is specified, and the SCore-S library detects a
panic situation or an exceptional signal, then SCore-S tries
to invoke a GDB and let it attach to the user
program. DISPLAY shell environment variable is
expected to be set properly, so that xterm under which
GDB runs can display a window on your host.
- Environment Variables
Option string specified in the command argument is analyzed,
then SCore-S tries to get option string from this shell
environment variable also.
If the user program is to run under SCore-D, the value of this
shell environment variable is taken as option string too.
SCore does not try to detect if any other users login and CPU
consumption. If so, your program execution speed may slowdown. It is
users etiquettes that you do not run a text editor or compiler on the
cluster hosts if some other user is using the cluster. Use
msgb to see which cluster hosts are
in use, or use msgblock to lock
host(s) for running non-SCore programs.
The total number of option settings is limited by maximum transmission
unit of communication library.
- SEE ALSO
SCore-D User Manual
Real World Computing Partnership
Parallel Distributed System Software Tsukuba Laboratory
$Id: score-user.html,v 1.12 1998/06/02 11:50:41 kameyama Exp $