LSF Version 7.3 - Administering Platform LSF

Administering Platform LSF 441
Advance Reservation
If an advance reservation is modified, preemption is done for an active advance
reservation after every modification of the reservation when there is at least one
pending or suspended job associated with the reservation.
When slots are added to an advance reservation with
brsvmod, LSF preempts
running non-reservation jobs if necessary to provide slots for jobs belonging to the
reservation. Preemption is triggered if there are pending or suspended jobs
belonging to the reservation in the system.
When preemption is triggered, non-advance reservation jobs are suspended and
their slots given to the advance reservation on the hosts belonging to the
reservation. On each host, enough non-advance reservation jobs are suspended so
that all of slots required by the advance reservation are obtained. The number of
slots obtained does not depend on the number of jobs submitted to the advance
reservation. Non-advance reservation jobs on a host can only to use slots not
assigned to the advance reservation.
If you run suspend running a non-reservation job with
bstop, you cannot resume
it with
bresume while the reservation is active.
When a job is preempted for an advance reservation, it can only resume on the host
when either the advance reservation finishes, or some other non-advance
reservation job finishes on the host.
For example, a single-host cluster has 10 slots, with 9 non-advance reservation jobs
dispatched to the host (each requiring one slot). An advance reservation that uses
5 slots on the host is created, and a single job is submitted to the reservation. When
the reservation becomes active, 4 of the non-advance reservation jobs are
suspended, and the advance reservation job will start.
Forcing a job to run before a reservation is active
LSF administrators can use brun to force jobs to run before the reservation is active,
but the job must finish running before the time window of the reservation expires.
For example, if the administrator forces a job with a reservation to run one hour
before the reservation is active, and the reservation period is 3 hours, a 4 hour run
limit takes effect.
Advance reservations across clusters
You can create and use advance reservation for the MultiCluster job forwarding
model. To enable this feature, you must upgrade all clusters to LSF Version 7 or
later.
See the Using Platform LSF MultiCluster for more information.
View historical accounting information for advance reservations
1 Use the -U option of the bacct command to display accounting information
about advance reservations.
bacct -U summarizes all historical modification of the reservation and
displays information similar to the
brsvs command:
◆ The reservation ID specified on the -U option.
◆ The type of reservation: user or system