# Analysis: CPU Load Analysis
## CPU Load Analysis
For D < T , the biggest period during which the CPU is permanently used (i.e. without interruption, idle time) corresponds to the scenario in which all tasks are activated synchronously. This period is called **synchronous busy period** and has duration L.
L can be computed by the following iterative method, which returns the first instant since the synchronous activation in which the CPU completes all the submitted jobs.
{% hint style="info" %}
#### Computation of L
{% endhint %}
Knowing L, we have to guarantee the **Load Condition** , i.e.
The Load Condition refers to all the work that must be **completed by t**.
### How to compute h(t)?
Example:
* Task set Γ = {(2, 4), (2, 8), (3, 16)}.
* Draw the Gantt chart and mark the points where tasks must complete.
* Write a suitable equation.
Knowing L we have to guarantee the load condition, i.e.
And h(t) can be computed as follows:
The computation of h(t) for all values of t ∈ \[0, L\[ is unfeasible.
* However it is enough computing the load condition for the instants in which the load function varies, i.e.
Note: there are other, possibly shorter, values for L.
## EDF Scheduling
 -> Schedulability not guaranteed.
But the CPU load analysis indicates that the task set is schedulable!
