Your account balance is printed each time you login, so you might see your account balance heading toward zero quickly if you are using large numbers of processors per job or running large numbers of jobs. Your group account balance should only go negative if your group has used more computer time than you had purchased. (This limit is calculated based upon 100% utilization for the equipment you purchased, and even this limit has been exceeded.) To allow your group to continue means that you are definitely using resources purchased by some other group. The partnership allows this as long as the use is non-priority, meaning that it does not interfere with the ability of groups which have not used up their account to use the resources. This policy that the HPC Partners approved is implemented as follows: The process for groups who have a balance go negative is: 1) When the group balance is negative you get a warning on login. 2) When balance is less than -3000 all jobs are automatically routed to the low priority queue. On lightning3, the low priority queue allows small jobs, using either nodes=1:ppn=16:ib,walltime=24:00:00 or nodes=1:ppn=32:noib,walltime=24:00:00 (noib runs on a slower 128GB node with no infiniband) A job submitted which exceeds these limits will be rejected. The low priority queue only allows a SINGLE running job over ALL users.