Guaranteed start time allows you to specify when your environment will start. There are limitations on the number of jobs that can be combined for a guaranteed start time. Also, each job must be a single requirement job. The process of guaranteeing a start time requires that jobs be attached to a virtual container (VC). Only jobs or workflows belonging directly to the VC will be scheduled.

To guarantee start time, do the following:

1. Create a virtual container (VC).

   > mvcctl -c

2. Set the holdjobs flag on the VC to prevent jobs from immediately running.

   > mvcctl -m flags+=holdjobs <VCNAME>

3. Submit the job(s).

   > msub -W x=vc=<VCNAME> . . .

4. (Optional Step) Specify a start time as epoch or relative (+) via the reqstarttime attribute.

   > mvcctl -m reqstarttime=<epoch | +{mm:ss}>

5. Schedule the VC.

   > mvcctl -x schedulevc <VCNAME>

   There is a default limit of five jobs that can be combined for guaranteed start time.