FairShare Groups

In Accelerator, FairShare groups are managed by either the information in the vnc.swd directory that contains the policy.tcl file, or the vovfsgroup utility. Every user has a default FairShare group, which is set in the policy.tcl file. Use nc run with the option -g to select a different group. An error occurs if the user specifies a non-existent group or a group to which the user does not belong.

For example:

% nc cmd vovshow -users
% nc run -g /time/regression sleep 10
% nc run -g xxxx sleep 10
nc: USER ERROR: No such group defined: 'xxxx'

FairShare Subgroups

Subgroups can be specified by using the -sg option. Subgroups can be created at submit time as opposed to groups , which must be defined ahead of time. Subgroups allow a user to allocate shares of computing resources to subsets of their own workload.

For example:

% nc run -sg subgroup sleep 10                      (/time/users.john:subgroup)
% nc run -g /time/regression -sg subgroup sleep 10  (/time/regression.john:subgroup)