Job (Scheduling)

computation scheduling

Definition

Job

A job in scheduling is a unit of work that must be assigned to a machine and, depending on the model, to a time interval.

Formally, a scheduling instance has a finite job set

$$J=\{1,\dots ,n\}.$$

Each job $j\in J$ may carry parameters such as processing time $p_j$, release time $r_j$, deadline $d_j$, weight $w_j$, or a fixed interval $[s_j,f_j)$.

Parameters

Common data

A job is described by the data needed by the scheduling model:

• $p_j$: processing time;
• $r_j$: release time;
• $d_j$: deadline or due date;
• $w_j$: weight or priority;
• $[s_j,f_j)$: fixed interval.

Role

In interval scheduling and interval partitioning, a job is already tied to a fixed interval. The schedule does not choose its start time; it only chooses whether to accept it, or which machine receives it.