Update MATLAB Job Scheduler Startup Parameters
The scripts for the mjs
service run using several default parameters that
you can define in the mjs_def
file. The parameters in the
mjs_def
file allow you to customize the features in your MATLAB® Job Scheduler.
For example, you can modify the mjs_def
file to:
Set cluster security.
Adjust job scheduling and resource utilization settings.
Configure parameters to support dynamic scaling based on workload requirements.
Export metrics for live cluster monitoring and alerts.
If this is the first time you start MATLAB Job Scheduler, modify the mjs_def
file before you start the
mjs
service, job manager, and workers. If you already have a MATLAB Job Scheduler running in your cluster, follow these instructions to stop the
existing scheduler service, modify the mjs_def
file, and restart the
mjs
service to apply your changes.
In the following instructions, matlabroot
refers to the
location of your installed MATLAB
Parallel Server™ software. Where you see this term used in the instructions that follow,
substitute the path to your location.
Modify mjs_def
File
You can find the mjs_def
file in these locations:
on Microsoft® Windows® operating systemsmatlabroot
\toolbox\parallel\bin\mjs_def.bat
on Linux® operating systems.matlabroot
/toolbox/parallel/bin/mjs_def.sh
You can edit the mjs_def
file to update the default parameters
before starting the mjs
service. To learn more about all the user
configurable parameters in the mjs_def
file, see Define MATLAB Job Scheduler Startup Parameters.
The mjs
service reads the mjs_def
file when you start
or stop the mjs
service, run the mjs
service with the
console
option, or install or uninstall the mjs
service
on a Windows operating system. When you start and stop workers and job managers, they contact
the mjs
service they are running under to obtain the values of the
definitions and defaults stored in this file. Thus, the mjs
service does not
read the mjs_def
file again when you start and stop workers and job managers.
When you make a change to the mjs_def
file, you must restart the
mjs
service, job manager and workers on each node to apply your
changes.
Note
For a working cluster setup, the mjs_def
file must use consistent
settings across all nodes of the cluster. If you have a shared file system, all nodes can point
to the same mjs_def
file.
If this is the first time you start MATLAB Job Scheduler, to start the mjs
service, job manager, and
workers, see Start MATLAB Job Scheduler Services.
If you already have a MATLAB Job Scheduler running in your cluster, stop the mjs
service,
job manager and workers of the existing MATLAB Job Scheduler, edit the mjs_def
file, then restart the
mjs
service, job manager, and workers to apply your changes. For
instructions, see Stop and Restart MATLAB Job Scheduler Services.
Stop and Restart MATLAB Job Scheduler Services
To stop the
mjs
service, job manager, and workers, select one of these options:Make the required changes to the
mjs_def
file.To restart the
mjs
service, job manager, and workers, select one of these options:
Start MATLAB Job Scheduler Services
If this is the first time you start MATLAB Job Scheduler, after you have made the required changes to the
mjs_def
file, select one of these options to start the
mjs
service, job manager and workers.
Specify an Alternative mjs_def
File
Alternatively, you can make a copy of the mjs_file
file, modify the
copy, and specify that this copy be used for the default parameters.
To start the mjs
service with the alternative defaults file, specify the
file in the mjs
command.
On Linux operating systems, enter the command:
mjs start -mjsdef my_mjs_def.sh
On Windows operating systems, enter the command:
mjs install -mjsdef my_mjs_def.bat mjs start -mjsdef my_mjs_def.bat
If you specify a new mjs_def
file instead of the default file for the
service on one computer, the new file is not automatically used by the mjs
service on other computers. If you want to use the same alternative file for all your
mjs
services, you must specify it for the mjs
service you
start on each cluster node.
Note
The startup script flags take precedence over the settings in the
mjs_def
file.
Start in a Clean State
When a job manager or worker starts up, it normally resumes its session from the past. This way, a job queue is not destroyed or lost if the job manager machine crashes or if the job manager is inadvertently shut down. However, there are situations where an admin might want to start a job manager in a clean state. For instance, if the job manager's state is corrupted or contains errors, starting from a clean state can resolve these issues.
To start up a job manager or worker from a clean state, with all history deleted, use the
-clean
flag on the startjobmanager
and
startworker
commands. This deletes all checkpoint information stored on
disk from previous instances of this job manager and workers before starting. The job manager
initializes with no existing jobs or tasks.
startjobmanager -clean -name MyJobManager startworker -clean -jobmanager MyJobManager
Note
Using the -clean
flag permanently removes all existing job data. Be
sure this data is no longer needed before removing it.