Administering Platform LSF - SAS

Checkpointing Jobs
Checkpointing Jobs
Fault tolerance
Checkpointing a job involves capturing the state of an executing job, the data
necessary to restart the job, and not wasting the work done to get to the current
stage. The job state information is saved in a checkpoint file. There are many
reasons why you would want to checkpoint a job.
To provide job fault tolerance, checkpoints are taken at regular intervals
(periodically) during the job’s execution. If the job is killed or migrated, or if
the job fails for a reason other than host failure, the job can be restarted from
its last checkpoint and not waste the efforts to get it to its current stage.
Migration
Checkpointing enables a migrating job to make progress rather than restarting
the job from the beginning. Jobs can be migrated when a host fails or when a
host becomes unavailable due to load.
Load balancing
Checkpointing a job and restarting it (migrating) on another host provides load
balancing by moving load (jobs) from a heavily loaded host to a lightly loaded
host.
In this section ◆ “Approaches to Checkpointing” on page 309
◆ “Checkpointing a Job” on page 313
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Administering Platform LSF