lsn_max_multiplicity.h File Reference

Maximum sustainable multiplicity (concurrency level) of every element of a layered software network. More...

#include <cstddef>
#include <deque>
#include <vector>
#include "line/num/number.h"
#include "line/util/error.h"
#include "line/util/matrix.h"

Include dependency graph for lsn_max_multiplicity.h:

Go to the source code of this file.

Classes
struct	line::lsn::Multiplicity< T >
	A multiplicity, possibly infinite; MATLAB's mult(i) = Inf. More...
struct	line::lsn::LsnInput< T >
	The plain-data fields of a layered software network read by the algorithm. More...

Namespaces
namespace	line
namespace	line::lsn

Enumerations
enum class	line::lsn::LsnElementType {   line::lsn::HOST = 0 , line::lsn::TASK = 1 , line::lsn::ENTRY = 2 , line::lsn::ACTIVITY = 3 ,   line::lsn::CALL = 4 }
	Element kinds, with the values of MATLAB's LayeredNetworkElement. More...

Functions
template<class T>
Multiplicity< T >	line::lsn::mult_add (const Multiplicity< T > &a, const Multiplicity< T > &b)
	a + b, with infinity absorbing.
template<class T>
Multiplicity< T >	line::lsn::mult_min (const Multiplicity< T > &a, const Multiplicity< T > &b)
	min(a,b), with infinity as the top element.
template<class T>
std::vector< Multiplicity< T > >	line::lsn::lsn_max_multiplicity (const LsnInput< T > &lsn)
	Maximum sustainable multiplicity (concurrency level) of every element of a layered software network.

Detailed Description

Maximum sustainable multiplicity (concurrency level) of every element of a layered software network.

Templated port of matlab/src/api/lsn/lsn_max_multiplicity.m, cross-checked against jar/src/main/java/jline/api/lsn/LsnMaxMultiplicity.java. It lives under api/lqn/ because the port adds no api/lsn/ directory of its own; the namespace is line::lsn, matching the MATLAB domain.

Concurrency is propagated along the call graph in topological order (Kahn): a reference task seeds its own multiplicity, an entry with open arrivals seeds one thread, and every element passes on min(what reaches it, what it can hold). A setup task is exempt from the caller bound: its instances are provisioned by the platform rather than spawned by its callers, so it passes on its declared multiplicity. A non-reference task with infinite multiplicity ends up unbounded.

SCOPE: the port takes the six plain-data fields the algorithm actually reads – the call graph, the multiplicities, the element types, the reference and setup-task flags, and the per-entry open-arrival flag – rather than a LayeredNetworkStruct, so no model layer is needed.

DIVERGENCE, MATLAB vs JAR: MATLAB also seeds inflow(i) = 1 for an ENTRY that has an open arrival (lsn.arrival{i} non-empty); the JAR omits that branch entirely, so an open-arrival entry reachable from no reference task gets outflow 0 there and 1 in MATLAB. This port follows MATLAB, the reference implementation, and exposes the flag as entry_has_arrival.

ARITHMETIC: comparisons and additions only, so a finite field computation, exact in the exact instantiation. Infinite multiplicity is carried by an explicit flag instead of a floating infinity, both because Rational has no infinity and because Inf + Inf and min(Inf, Inf) are then decided by the algorithm rather than by the number type.

Definition in file lsn_max_multiplicity.h.