A usage reservation can be used to place a hold on the user's account before usage starts to ensure that the credits will be there when it completes. The replace option may be specified if you want the new reservation to replace existing reservations of the same instance name (associated with the same usage record). The modify option may be specified to dynamically extend any existing reservation with the same instance name with the specified characteristics instead of creating a new one. See Managing Reservations for more information about these options.

To create a job reservation use the command greserve:

greserve [-T usage_record_type] [-u user_name] [-g group_name] [-p project_name] [-o organization] [-c class_name] [-Q quality_of_service] [-m machine_name] [-N nodes] [-P processors] [-M memory] [-D disk] [-n network] [-X, --extension property name=property_value[,property_name=property_value...]] [-t reservation_duration] [-G grace_duration]] [-s reservation_start_time] [-e reservation_end_time] [-d reservation_description] [-z reservation_amount] [--itemizedCharges itemized_charges] [--replace|--modify] [-R charge_rate_type:charge_rate_name[{charge_rate_instance}]=charge_rate_amount[,charge_rate_type:charge_rate_name[{charge_rate_instance}]=charge_rate_amount...]] [--debug] [-?, --help] [--man] [--quiet] [-v, --verbose] [-V, --version] [-q quote_id] [[-j] usage_record_id] {-J] instance_name|job_id}

Additional detail for this command can be found in the man page by issuing greserve --man at the command line.

Example 7. Creating a reservation

$ greserve -J PBS.1234.0 -p chemistry -u amy -m colony -P 2 -t 3600
Successfully reserved 7200 credits with reservation id 37 for instance PBS.1234.0 and created usage record id 87