Package jline.api.lqn

Class Lqn_focus

java.lang.Object
jline.api.lqn.Lqn_focus
public final class Lqn_focus extends Object
Focused layered performance model by aggregation (FSPT), port of MATLAB lqn_focus.

Reduces a LayeredNetwork to a focused model (FM) that keeps a set of preserved tasks and hosts unchanged and replaces every other task by one aggregate task per dependency group, following Islam, Petriu and Woodside, "Focused Layered Performance Modelling by Aggregation", ACM TOMPECS 2022.

The original model (OM) is solved once with SolverLN to obtain the saturations S = U/m of every task and host. The preserved set is chosen by the sat (SATr: forced elements plus every resource with S > Smax/r), acc (ACCx: forced elements plus the i most saturated resources, i grown until the reference-task throughput error is below x) or manual (forced elements, the most saturated resource and preserve) strategy. A preserved task preserves its host and a preserved host all of its tasks. Tasks using features FSPT does not aggregate (priorities, AND forks/joins, second phases, asynchronous calls, forwarding, open arrivals, replication, fan-in or fan-out, setup/delay-off and activity think times) are always preserved.

Non-preserved tasks with the same set Pi(T) of preserved tasks depending on them form a group, replaced by one aggregate task with one entry and one activity (eqs. 7-11). A host shared by several groups is split into shadow hosts of speed s_H (1 - saturation by the other groups) (eq. 15), or preserved when that capacity is not positive.

Since:
LINE 3.0