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Fairshare is a tree. There are fairshare groups and entities (e.g., users). A job belongs to one entity. Each fairshare group has children which can be either another fairshare group or an entity. All entities don't have to be at the same level. For example, root can have 3 children which are two groups and one entity. The two groups will have entities within them. Each group or entity has a number of shares assigned to them. This is a relative percentage between the siblings of that group. Each entity has a fairshare target (fairshare_perc). The relative percentage between siblings times the parents fairshare_perc parent's target is the entity/group's fairshare_perctarget. The shares are turned into a fairshare target (fairshare_perc) which is a percentage number between 0 and 1. If you add up all the targets of all of the entities, you will reach 100%.
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