Q. Why is my credit balance now negative?

A. If your credits are fully exhausted while a calculation is in progress, the job will be stopped. Credit balance checks are not performed in real-time but are done at one-hour intervals. Therefore, based on the computing resources used, a negative credit balance of up to $0.25 per Spot Instance ($0.50 per On-Demand Instance) * PPN can occur. Negative credits do not automatically get charged, but if the credit balance is negative, new jobs cannot be submitted. Therefore, users must recharge credits in the ‘Account>Credits Management’ section.

For subscription plans that provide unlimited servers, such as GRAPHENE-330, FULLERENE-660, and DIAMOND-990, the provided CPU time is used up first, and then the unlimited servers are utilized. If the number of cores being used for a job matches the number of cores available on the unlimited server at the time the provided CPU time is fully used, the job will connect to the unlimited server without interruption. However, if the number of cores in use does not match the number of cores on the unlimited server, the job will not be automatically directed to an unlimited server and your credits will be deducted. Running out of credits could result in a negative balance, and your job may be stopped as a consequence. Therefore, we recommend that you adjust your job to use a number of cores that match the unlimited server before your allocated CPU time is fully consumed.