Maui Scheduler

12.1 Node Location

Nodes can be assigned three types of location information based on partitions, frames, and/or queues.

12.1.1 Partitions

The first form of location assignment, the partition, allows nodes to be grouped according to physical resource constraints or policy needs. By default, jobs are not allowed to span more than one partition so partition boundaries are often valuable if a underlying network topology make certain resource allocations undesirable. Additionally, per-partition policies can be specified to grant control over how scheduling is handled on a partition by partition basis. See the Partition Overview for more information.

12.1.2 Frames

Frame based location information is orthogonal to the partition based configuration and is mainly an organizational construct. In general frame based location usage, a node is assigned both a frame and a slot number. This approach has descended from the IBM SP2 organizational approach in which a frame can contain any number of slots but typically contains between 1 and 64. Using the frame and slot number combo, individual compute nodes can be grouped and displayed in a more ordered manner in certain Maui commands (i.e., showstate). Currently, frame information can only be specified directly by the system via the SDR interface on SP2/Loadleveler systems. In all other systems, this information must be manually specified via the NODECFG parameter.


# maui.cfg


When specifying node and frame information, slot values must be in the range of 1 to 32 (limited to 1 to 16 in Maui 3.0 and earlier). and frames must be in the range of 1 to 64.

12.1.3 Queues

Some resource managers allow queues (or classes) to be defined and then associated with a subset of available compute resources. With such systems, such as Loadleveler or PBSPro, these queue to node mappings are automatically detected. On resource managers which do not provide this service, Maui provides alternative mechanisms for enabling this feature. OpenPBS Queue to Node Mapping

Under OpenPBS, queue to node mapping can be accomplished setting the queue acl_hosts parameter to the mapping hostlist desired within PBS. Further, the acl_host_enable parameter should be set to False. NOTE: Setting acl_hosts and then setting acl_host_enable to True will constrain the list of hosts from which jobs may be submitted to the queue. Prior to Maui 3.0.7p3, queue to node mapping was only enabled when acl_host_enable was set to True, thus, for these versions, the acl_host list should always include all submission hosts.