Support capacity constrained planning

[ushnisha]

Support capacity constrained planning

[ushnisha]

Fixed with commit: ab467cc

Basic support for capacity planning has been provided. A brief description of the unconstrained and constrained planning algorithms are given below.

The description is at a single Task/Workcenter/Taskplan level for one direction of propagation of requests upstream; but a similar logic applies when propagation the promises downstream too.

(1) Unconstrained Planning:

• When a task receives a request, it is automatically planned based on just lead time if it loads no workcenters.

• If it loads workcenters, then the task will plan based on the calendar constraints (holidays and efficiency) of its primary workcenters.

• No check is made to see if the primary workcenter is already loaded by another taskplan during this time.

• If a task cannot be planned because it will have to start before plan start (because of lead time, holiday and efficiency considerations), then the task will be planned by looking forward in time from plan start. This effect will also be propagated to downstream taskplans.

(2) Constrained Planning:

• When a task receives a request; it first performs a request to each of the associated workcenters (not just the primary workcenter).

• The request is first made to the primary workcenter.

• If the primary workcenter automatically satisfied the request (without any delays), then we propagate this plan upstream.

• If the primary workcenter is unable to meet the request on time, we query the other workcenters in order of priority until we get the best date possible.

• When the workcenter receives a request from a task, it checks not only the holiday schedule and the efficiency, it also makes sure that there are no other task plans that intersect with this requested date range when we plan this TaskPlan.

• If there are conflicts, the workcenter will look first for earlier capacity availability (build ahead) and if there is none, it will try to look for later capacity (build late).