How can we guarantee that a group of users (or a project) a minimum of X nodes available

Users/Site Administrators
1

As a working example, let us consider we have 100 nodes and 2 groups for which we should guarantee 10 nodes each.

How could this be implemented in PBS?

2

Case 1:
1 . Create two queues with ACLS
2. Qlist + 10 nodes to each of the queues
3. Make sure other 80 nodes are not part of this Qlist

Case 2:

  1. Create two reservation queues each with 10 nodes assigned to it and enable ACL on those queues
  2. rest the nodes can be utilised by users in the group(s)

Case 3:

  1. write hook(s) that keep track of mapping of - nodes and group of users and their jobs

Hope these cases help. There might be other custom solutions as well

3

Hi Adarsh,
thanks for reply
please consider one scenarios so how can we do

In the example scenario, we have:

  • 2 specific user groups and the remaining mass of other users
  • The cluster size is 100 nodes
  • The 2 groups must have a guaranteed minimum capacity of 10 nodes
  • The job size of each job is 6 nodes
  • All users have constantly jobs waiting to be placed by the scheduler into the cluster
  • With the given job size of 6 nodes we have:
    • The pool for all users (whether in a specific group or not) is 80 nodes
      • 100 [nodes total] – 2 [number of groups] * 10 [nodes for each specific group] = 80 nodes
    • a maximum of 13 jobs (job size 6 nodes) could be placed for users whether in a specific group or not:
      • 13 * 6 = 78 nodes
    • With the guaranteed 10 nodes, group A and B can always run a minimum of 1 job
    • This results in a remaining capacity for group A or B of 6 nodes, suitable to place 1 further job
      • 2 nodes from the pool for all and 4 nodes from the guaranteed pool, could support a further 6 node job
        • ( 80 nodes in total for all users; maximum utilization for all users is 78 nodes (see above), so 80 -78 = 2 nodes)
        • 10 nodes guaranteed for each special group; 1 node fits completely in this limit => 10 -6 = 4 nodes
      • => 1 additional job, whether from group A or from group B, could run in the cluster
        • In this scenario, 4 nodes would not be utilized, as these are in the pool of one of the special groups.

What kind of configuration could ensure a utilsataion of 96 nodes in this scenario ?

regards
deepak