User`s guide

6 Programming Overview

6-8

Cluster

Client

Worker

Job

createJob

submit

Pending

Queued Running

Finished

fetchOutputs

Worker

Stages of a Job

The following table describes each stage in the life cycle of a job.

Job Stage Description

Pending You create a job on the scheduler with the createJob function in

your client session of Parallel Computing Toolbox software. The

job's first state is pending. This is when you define the job by

adding tasks to it.

Queued When you execute the submit function on a job, the MJS or

scheduler places the job in the queue, and the job's state is

queued. The scheduler executes jobs in the queue in the sequence

in which they are submitted, all jobs moving up the queue as the

jobs before them are finished. You can change the sequence of the

jobs in the queue with the promote and demote functions.

Running When a job reaches the top of the queue, the scheduler distributes

the job's tasks to worker sessions for evaluation. The job’s state is

now running. If more workers are available than are required for

a job's tasks, the scheduler begins executing the next job. In this

way, there can be more than one job running at a time.

Finished When all of a job’s tasks have been evaluated, the job is moved

to the finished state. At this time, you can retrieve the results

from all the tasks in the job with the function fetchOutputs.