LSF Version 7.3 - Administering Platform LSF

Understanding Advance Reservations
422 Administering Platform LSF
Understanding Advance Reservations
Advance reservations ensure access to specific hosts during specified times. During
the time that an advanced reservation is active only users or groups associated with
the reservation have access to start new jobs on the reserved hosts.
Only LSF administrators or root can create or delete advance reservations. Any LSF
user can view existing advance reservations.
Each reservation consists of the number of job slots to reserve, a list of hosts for the
reservation, a start time, an end time, and an owner. You can also specify a resource
requirement string instead of or in addition to a list of hosts.
Active reservations
When a reservation becomes active, LSF attempts to run all jobs associated with the
reservation. By default jobs running before the reservation became active continue
to run when the reservation becomes active. When a job associated with the
reservation is pending because not enough job slots are available, LSF suspends all
jobs not associated with the reservation that are running on the required hosts.
During the time the reservation is active, only users or groups associated with the
reservation have access to start new jobs on the reserved hosts. The reservation is
active only within the time frame specified, and any given host may have several
reservations in place, some of which may be active at the same time.
Jobs are suspended only if advance reservation jobs require the slots. Jobs using a
reservation are subject to all job resource usage limits, but any resources freed by
suspending non-advance reservation jobs are available for advance reservation jobs
to use.
Closed and open reservations
Reservations are typically closed. When a closed reservation expires, LSF kills jobs
running in the reservation and allows any jobs suspended when the reservation
became active to run.
Open advance reservations allow jobs to run even after the associated reservation
expires. A job in the open advance reservation is only be treated as an advance
reservation job during the reservation window, after which it becomes a normal
job. This prevents the job from being killed and makes sure that LSF does not
prevent any previously suspended jobs from running or interfere with any existing
scheduling policies.
Jobs running in a one-time open reservation are detached from the reservation and
suspended when the reservation expires, allowing them to be scheduled as regular
jobs. Jobs submitted before the reservation became active are still suspended when
the reservation becomes active. These are only resumed after the open reservation
jobs finish.
Jobs running is a closed recurring reservation are killed when the reservation
expires.
Jobs running in an open recurring reservation are suspended when the reservation
expires, and remain pending until the reservation becomes active again to resume.