Suspension of jobs

After running the first job for several hours on GPU, I want to suspend this job and instead let
run other person’s jobs. After other person’s jobs are finished after several hours, I want
to resume the first job. I use cuda-7.5 with GTX-980Ti. I use the DEFAULT mode.

If I suspend the first job, nvidia-smi shows still the first job as if it is running
still which consumes the graphics memory. If this consumption is big, other person seems
not to be able to run their jobs.

I would like to know whether this kind of suspension is possible or not.