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NCSA Policy regarding Co-scheduling

Available resources

IA-64 Cluster (mercury)

Available opportunities

Reservations may be made any time

Minimum advance notice to make a reservation

No restrictions. However, please take into consideration that the scheduler and other back end processes may take 5-10 minutes to complete actions associated with the reservation, so allow a buffer period for making a reservation before submitting a job to run within that reservation.

Reservation size

Maximum nodes: 256 (512 processors)
Maximum wall clock time: 24 hours

Reservation charges

The charge for a reservation is the number of processors used * wall clock time.

Usage will be charged for the entire interval of the reservation whether the reservation is used or not. If any unsed portion of a reservation is cancelled no charge will be made for the unused portion of the reservation

Example: A user requesting a reservation for a 64-node job using 4 hours will be charged 4 * 64 = 256 SUs

Cancellation refunds

A reservation can be cancelled at any time and a no charges will be made for any unused portion of the reservation.

Collective machine limits

A total of 256 nodes (512 processors) can be reserved at any one time by any combination of users.

Run-time limits

Your entire job request must run within the allotted reservation time. This includes a few minutes for the scheduler and other back end processes to complete initial activities at the beginning of your job. So allow for 5-10 minutes at the start. Examples:

A 3-hour job that is submitted within 2 hours of the end of your reservation will not start. If you submit a job with a wall clock time of 18 hours exactly at the start of your 18-hour reservation, it will not run; if you submit it with a wall clock time of 17 hours and 50 minutes, it should start.