Revert "Added Unavailable times"

This reverts commit c4d7f04d0d.
This commit is contained in:
2025-01-28 16:23:55 +01:00
parent c4d7f04d0d
commit 4866864808
8 changed files with 90 additions and 247 deletions

View File

@@ -29,21 +29,13 @@ public class Main {
csv = arguments.get("csv");
var parallel = arguments.containsKey("p");
// varius distributions
var distrExp = new Distribution.Exponential(lambda);
var distrNorm = new Distribution.NormalBoxMuller(mu, sigma);
var distrUnav = new Distribution.UnavailableTime(0.2, distrNorm);
// Build the network
var net = new Net();
var node1 = ServerNode.createLimitedSource("Source", distrExp, total);
var node2 = ServerNode.createQueue("Queue", 1, distrNorm);
var node3 = ServerNode.createQueue("Queue Wait", 1, distrNorm, distrUnav);
var node1 = ServerNode.createLimitedSource("Source", new Distribution.Exponential(lambda), total);
var node2 = ServerNode.createQueue("Queue", 1, new Distribution.NormalBoxMuller(mu, sigma));
net.addNode(node1);
net.addNode(node2);
net.addNode(node3);
net.addConnection(node1, node2, 1.0);
net.addConnection(node2, node3, 1.0);
net.normalizeWeights();
/// Run multiple simulations

View File

@@ -4,34 +4,8 @@ package net.berack.upo.valpre.rand;
* Represents a probability distribution.
*/
public interface Distribution {
/**
* Return a sample from the distribution.
*
* @param rng The random number generator to use.
* @return A number given from the distribution.
*/
public double sample(Rng rng);
/**
* Gets a positive sample from the distribution.
* This is useful if you need to generate a positive value from a distribution
* that can generate negative values. For example, the normal distribution.
*
* @param distribution The distribution to sample
* @param rng The random number generator to use.
* @return A positive or 0 value from the distribution.
*/
public static double getPositiveSample(Distribution distribution, Rng rng) {
if (distribution == null)
return 0;
double sample;
do {
sample = distribution.sample(rng);
} while (sample < 0);
return sample;
}
/**
* Represents an exponential distribution.
*/
@@ -198,30 +172,4 @@ public interface Distribution {
return -Math.log(rng.random()) / lambdas[i];
}
}
/**
* TODO
*/
public static class UnavailableTime implements Distribution {
public final double probability;
public final Distribution distribution;
/**
* TODO
*
* @param probability
* @param distribution
*/
public UnavailableTime(double probability, Distribution distribution) {
this.probability = probability;
this.distribution = distribution;
}
@Override
public double sample(Rng rng) {
if (rng.random() < this.probability)
return Distribution.getPositiveSample(this.distribution, rng);
return 0.0;
}
}
}

View File

@@ -5,7 +5,6 @@ package net.berack.upo.valpre.sim;
*/
public class Event implements Comparable<Event> {
public final double time;
public final double started;
public final Type type;
public final ServerNode node;
@@ -16,11 +15,10 @@ public class Event implements Comparable<Event> {
* @param node The node that the event is associated with.
* @param time The time at which the event occurs.
*/
private Event(Type type, ServerNode node, double now, double time) {
private Event(Type type, ServerNode node, double time) {
this.type = type;
this.time = time;
this.node = node;
this.started = now;
}
@Override
@@ -32,40 +30,39 @@ public class Event implements Comparable<Event> {
return 1;
}
/**
* Create a new event.
*
* @param node The node that the event is associated with.
* @param time The time at which the event occurs.
* @param type The type of event.
*
* @return The new event.
*/
public static Event newType(ServerNode node, double time, Type type) {
return new Event(type, node, time);
}
/**
* Create a new arrival event.
*
* @param node The node that the event is associated with.
* @param now The time at which the event has been created.
* @param time The time at which the event occurs.
* @return The new event.
*/
public static Event newArrival(ServerNode node, double now, double time) {
return new Event(Type.ARRIVAL, node, now, time);
public static Event newArrival(ServerNode node, double time) {
return new Event(Type.ARRIVAL, node, time);
}
/**
* Create a new departure event.
*
* @param node The node that the event is associated with.
* @param now The time at which the event has been created.
* @param time The time at which the event occurs.
* @return The new event.
*/
public static Event newDeparture(ServerNode node, double now, double time) {
return new Event(Type.DEPARTURE, node, now, time);
}
/**
* Create a new unavailable event.
*
* @param node The node that the event is associated with.
* @param now The time at which the event has been created.
* @param time The time at which the event occurs.
* @return The new event.
*/
public static Event newUnavailable(ServerNode node, double now, double time) {
return new Event(Type.UNAVAILABLE, node, now, time);
public static Event newDeparture(ServerNode node, double time) {
return new Event(Type.DEPARTURE, node, time);
}
/**
@@ -74,6 +71,5 @@ public class Event implements Comparable<Event> {
public static enum Type {
ARRIVAL,
DEPARTURE,
UNAVAILABLE,
}
}

View File

@@ -11,8 +11,7 @@ public class ServerNode {
public final String name;
public final int maxServers;
public final int spawnArrivals;
public final Distribution service;
public final Distribution unavailable;
public final Distribution distribution;
/**
* Creates a source node with the given name and distribution.
@@ -24,7 +23,7 @@ public class ServerNode {
* @return The created source node.
*/
public static ServerNode createSource(String name, Distribution distribution) {
return new ServerNode(name, Integer.MAX_VALUE, distribution, null, Integer.MAX_VALUE);
return new ServerNode(name, Integer.MAX_VALUE, distribution, Integer.MAX_VALUE);
}
/**
@@ -32,39 +31,25 @@ public class ServerNode {
* arrivals to spawn that are served by infinite servers (Integer.MAX_VALUE).
*
* @param name The name of the node.
* @param service The distribution of the inter-arrival times.
* @param distribution The distribution of the inter-arrival times.
* @param spawnArrivals The number of arrivals to spawn.
* @return The created source node.
*/
public static ServerNode createLimitedSource(String name, Distribution service, int spawnArrivals) {
return new ServerNode(name, Integer.MAX_VALUE, service, null, spawnArrivals);
public static ServerNode createLimitedSource(String name, Distribution distribution, int spawnArrivals) {
return new ServerNode(name, Integer.MAX_VALUE, distribution, spawnArrivals);
}
/**
* Creates a queue node with the given name, maximum number of servers, and
* distribution.
*
* @param name The name of the node.
* @param maxServers The maximum number of servers in the queue.
* @param service The distribution of the service times.
* @param name The name of the node.
* @param maxServers The maximum number of servers in the queue.
* @param distribution The distribution of the service times.
* @return The created queue node.
*/
public static ServerNode createQueue(String name, int maxServers, Distribution service) {
return new ServerNode(name, maxServers, service, null, 0);
}
/**
* Creates a queue node with the given name, maximum number of servers, and
* distribution.
*
* @param name The name of the node.
* @param maxServers The maximum number of servers in the queue.
* @param service The distribution of the service times.
* @param unavailable The distribution of the unavailable times after service.
* @return The created queue node.
*/
public static ServerNode createQueue(String name, int maxServers, Distribution service, Distribution unavailable) {
return new ServerNode(name, maxServers, service, unavailable, 0);
public static ServerNode createQueue(String name, int maxServers, Distribution distribution) {
return new ServerNode(name, maxServers, distribution, 0);
}
/**
@@ -75,14 +60,13 @@ public class ServerNode {
*
* @param name The name of the node.
* @param maxServers The maximum number of servers in the queue.
* @param service The distribution of the service times.
* @param unavailable The distribution of the unavailable times after service.
* @param distribution The distribution of the service times.
* @param spawnArrivals The number of arrivals to spawn.
* @throws NullPointerException if the distribution is null
*/
private ServerNode(String name, int maxServers, Distribution service, Distribution unavailable, int spawnArrivals) {
if (service == null)
throw new NullPointerException("Service distribution can't be null");
public ServerNode(String name, int maxServers, Distribution distribution, int spawnArrivals) {
if (distribution == null)
throw new NullPointerException("Distribution can't be null");
if (maxServers <= 0)
maxServers = 1;
if (spawnArrivals < 0)
@@ -90,9 +74,8 @@ public class ServerNode {
this.name = name;
this.maxServers = maxServers;
this.distribution = distribution;
this.spawnArrivals = spawnArrivals;
this.service = service;
this.unavailable = unavailable;
}
/**
@@ -103,18 +86,12 @@ public class ServerNode {
* @param rng The random number generator to use.
* @return A positive sample from the distribution.
*/
public double getServiceTime(Rng rng) {
return Distribution.getPositiveSample(this.service, rng);
}
/**
* Return the unavailable time after a service
*
* @param rng The random number generator to use.
* @return A positive or 0 value from the distribution.
*/
public double getUnavailableTime(Rng rng) {
return Distribution.getPositiveSample(this.unavailable, rng);
public double getPositiveSample(Rng rng) {
double sample;
do {
sample = this.distribution.sample(rng);
} while (sample < 0);
return sample;
}
/**
@@ -128,14 +105,6 @@ public class ServerNode {
return this.spawnArrivals > Math.max(0, numArrivals);
}
@Override
public boolean equals(Object obj) {
if (!(obj instanceof ServerNode))
return false;
var other = (ServerNode) obj;
return obj.hashCode() == other.hashCode();
}
@Override
public int hashCode() {
return this.name.hashCode();

View File

@@ -26,7 +26,7 @@ public final class Simulation {
* Creates a new run of the simulation with the given nodes and random number
* generator.
*
* @param states The nodes in the network.
* @param states The nodes in the network.
* @param rng The random number generator to use.
* @param criterias when the simulation has to end.
*/
@@ -75,18 +75,21 @@ public final class Simulation {
switch (event.type) {
case ARRIVAL -> {
state.queue.add(this.time);
state.stats.updateArrival(event, state.queue.size());
this.addDeparture(node, state);
state.stats.updateArrival(this.time, state.queue.size(), state.numServerBusy != 0);
if (state.numServerBusy < node.maxServers) {
state.numServerBusy++;
this.addDeparture(node);
}
}
case DEPARTURE -> {
var arrivalTime = state.queue.poll();
state.stats.updateDeparture(event, arrivalTime);
state.numServerBusy--;
var startService = state.queue.poll();
state.stats.updateDeparture(this.time, this.time - startService);
if (this.addUnavailable(node)) {
state.numServerUnavailable++;
if (state.numServerBusy > state.queue.size()) {
state.numServerBusy--;
} else {
this.addDeparture(node, state);
this.addDeparture(node);
}
var next = this.net.getChildOf(node, this.rng);
@@ -97,11 +100,6 @@ public final class Simulation {
this.addArrival(node);
}
}
case UNAVAILABLE -> {
state.numServerUnavailable--;
state.stats.updateUnavailable(event);
this.addDeparture(node, state);
}
}
}
@@ -145,42 +143,20 @@ public final class Simulation {
* @param node The node to create the event for.
*/
public void addArrival(ServerNode node) {
var event = Event.newArrival(node, this.time, this.time);
var event = Event.newArrival(node, this.time);
fel.add(event);
}
/**
* Adds a departure event to the future event list. The event is created based
* on the given node, and the delay is determined by the node's service
* distribution.
* on the given node, and the delay is determined by the node's distribution.
*
* @param node The node to create the event for.
*/
public void addDeparture(ServerNode node, NodeState state) {
if (state.canServeRequest(node)) {
state.numServerBusy++;
var delay = node.getServiceTime(this.rng);
var event = Event.newDeparture(node, this.time, this.time + delay);
fel.add(event);
}
}
/**
* Adds an unavailable event to the future event list if the delay is > 0.
* The event is created based on the given node, and the delay is determined by
* the node's unavailability distribution.
*
* @param node The node to create the event for.
* @return if the event has been added to the FEL.
*/
public boolean addUnavailable(ServerNode node) {
var delay = node.getUnavailableTime(rng);
if (delay > 0) {
var event = Event.newUnavailable(node, this.time, this.time + delay);
fel.add(event);
return true;
}
return false;
public void addDeparture(ServerNode node) {
var delay = node.getPositiveSample(this.rng);
var event = Event.newDeparture(node, this.time + delay);
fel.add(event);
}
/**
@@ -207,21 +183,7 @@ public final class Simulation {
*/
public static class NodeState {
public int numServerBusy = 0;
public int numServerUnavailable = 0;
public final Statistics stats = new Statistics();
public final ArrayDeque<Double> queue = new ArrayDeque<>();
/**
* TODO
*
* @param node
* @return
*/
public boolean canServeRequest(ServerNode node) {
var totalOccupied = this.numServerBusy + this.numServerUnavailable;
var canServe = node.maxServers > totalOccupied;
var hasRequests = this.numServerBusy < this.queue.size();
return canServe && hasRequests;
}
private final ArrayDeque<Double> queue = new ArrayDeque<>();
}
}

View File

@@ -31,7 +31,7 @@ public class Result {
this.simulationTime = time;
this.timeElapsedMS = elapsed;
this.nodes = nodes;
this.size = (int) Math.ceil(Math.max(Math.log10(this.simulationTime), 1));
this.size = (int) Math.ceil(Math.log10(this.simulationTime));
this.iFormat = "%" + this.size + ".0f";
this.fFormat = "%" + (this.size + 4) + ".3f";
}
@@ -56,8 +56,8 @@ public class Result {
* the statistics for each node in the network.
*/
public String getSummary() {
String[] h = { "Node", "Departures", "Avg Queue", "Avg Wait", "Avg Unavailable", "Avg Response", "Throughput",
"Utilization %", "Last Event" };
String[] h = { "Node", "Departures", "Avg Queue", "Avg Wait", "Avg Response", "Throughput", "Utilization %",
"Last Event" };
var table = new ConsoleTable(h);
for (var entry : this.nodes.entrySet()) {
@@ -67,7 +67,6 @@ public class Result {
iFormat.formatted(stats.numDepartures),
fFormat.formatted(stats.avgQueueLength),
fFormat.formatted(stats.avgWaitTime),
fFormat.formatted(stats.avgUnavailableTime),
fFormat.formatted(stats.avgResponse),
fFormat.formatted(stats.troughput),
fFormat.formatted(stats.utilization * 100),
@@ -87,7 +86,7 @@ public class Result {
if (tableHeader)
builder.append(
"Seed,Node,Arrivals,Departures,MaxQueue,AvgQueue,AvgWait,AvgUnavailable,AvgResponse,BusyTime,WaitTime,UnavailableTime,ResponseTime,LastEventTime,Throughput,Utilization\n");
"Seed,Node,Arrivals,Departures,MaxQueue,AvgQueue,AvgWait,AvgResponse,BusyTime,WaitTime,ResponseTime,LastEventTime,Throughput,Utilization\n");
for (var entry : this.nodes.entrySet()) {
var stats = entry.getValue();
builder.append(this.seed);
@@ -104,16 +103,12 @@ public class Result {
builder.append(',');
builder.append(stats.avgWaitTime);
builder.append(',');
builder.append(stats.avgUnavailableTime);
builder.append(',');
builder.append(stats.avgResponse);
builder.append(',');
builder.append(stats.busyTime);
builder.append(',');
builder.append(stats.waitTime);
builder.append(',');
builder.append(stats.unavailableTime);
builder.append(',');
builder.append(stats.responseTime);
builder.append(',');
builder.append(stats.lastEventTime);

View File

@@ -3,8 +3,6 @@ package net.berack.upo.valpre.sim.stats;
import java.util.function.BiFunction;
import java.util.function.Function;
import net.berack.upo.valpre.sim.Event;
/**
* TODO
*/
@@ -13,14 +11,12 @@ public class Statistics {
public double numDepartures = 0.0d;
public double maxQueueLength = 0.0d;
public double avgQueueLength = 0.0d;
public double unavailableTime = 0.0d;
public double busyTime = 0.0d;
public double waitTime = 0.0d;
public double responseTime = 0.0d;
public double lastEventTime = 0.0d;
// derived stats, you can calculate them even at the end
public double avgUnavailableTime = 0.0d;
public double avgWaitTime = 0.0d;
public double avgResponse = 0.0d;
public double troughput = 0.0d;
@@ -29,49 +25,39 @@ public class Statistics {
/**
* TODO
*
* @param event
* @param time
* @param newQueueSize
* @param updateBusy
*/
public void updateArrival(Event event, double newQueueSize) {
public void updateArrival(double time, double newQueueSize, boolean updateBusy) {
var total = this.avgQueueLength * this.numArrivals;
this.numArrivals++;
this.avgQueueLength = (total + newQueueSize) / this.numArrivals;
this.maxQueueLength = Math.max(this.maxQueueLength, newQueueSize);
if (updateBusy)
this.busyTime += time - this.lastEventTime;
this.lastEventTime = event.time;
this.lastEventTime = time;
}
/**
* TODO
*
* @param event
* @param time
* @param response
*/
public void updateDeparture(Event event, double arrivalTime) {
public void updateDeparture(double time, double response) {
this.numDepartures++;
this.responseTime += event.time - arrivalTime;
this.busyTime += event.time - event.started;
this.responseTime += response;
this.busyTime += time - this.lastEventTime;
this.lastEventTime = time;
this.waitTime = this.responseTime - this.busyTime;
this.avgWaitTime = this.waitTime / this.numDepartures;
this.avgResponse = this.responseTime / this.numDepartures;
this.troughput = this.numDepartures / event.time;
this.utilization = this.busyTime / event.time;
this.lastEventTime = event.time;
}
/**
* TODO
*
* @param event
*/
public void updateUnavailable(Event event) {
this.unavailableTime += event.time - event.started;
this.avgUnavailableTime = this.unavailableTime / event.time;
this.lastEventTime = event.time;
this.troughput = this.numDepartures / this.lastEventTime;
this.utilization = this.busyTime / this.lastEventTime;
}
/**
@@ -120,13 +106,11 @@ public class Statistics {
save.avgQueueLength = func.apply(val1.avgQueueLength, val2.avgQueueLength);
save.busyTime = func.apply(val1.busyTime, val2.busyTime);
save.responseTime = func.apply(val1.responseTime, val2.responseTime);
save.unavailableTime = func.apply(val1.unavailableTime, val2.unavailableTime);
save.waitTime = func.apply(val1.waitTime, val2.waitTime);
save.lastEventTime = func.apply(val1.lastEventTime, val2.lastEventTime);
// derived stats
save.avgWaitTime = func.apply(val1.avgWaitTime, val2.avgWaitTime);
save.avgResponse = func.apply(val1.avgResponse, val2.avgResponse);
save.avgUnavailableTime = func.apply(val1.avgUnavailableTime, val2.avgUnavailableTime);
save.troughput = func.apply(val1.troughput, val2.troughput);
save.utilization = func.apply(val1.utilization, val2.utilization);
}

View File

@@ -14,7 +14,7 @@ public class TestSimulation {
private static double DELTA = 0.0000001;
private static Rng rigged = new RiggedRng();
private static Distribution const0 = new Constant(0.0);
private static Distribution const1 = new Constant(1.0);
private static Distribution const1 = new Constant(0.0);
private final static class RiggedRng extends Rng {
@Override
@@ -38,7 +38,7 @@ public class TestSimulation {
@Test
public void serverNode() {
var node = ServerNode.createQueue("Nodo", 0, const1);
var node = new ServerNode("Nodo", 0, const1, 0);
assertEquals("Nodo", node.name);
assertEquals(1, node.maxServers);
assertFalse(node.shouldSpawnArrival(0));
@@ -46,7 +46,7 @@ public class TestSimulation {
assertFalse(node.shouldSpawnArrival(1000));
assertFalse(node.shouldSpawnArrival(Integer.MAX_VALUE));
assertFalse(node.shouldSpawnArrival(-1));
assertEquals(1.0, node.getServiceTime(null), DELTA);
assertEquals(1.0, node.getPositiveSample(null), DELTA);
node = ServerNode.createQueue("Queue", 50, const1);
assertEquals("Queue", node.name);
@@ -56,7 +56,7 @@ public class TestSimulation {
assertFalse(node.shouldSpawnArrival(1000));
assertFalse(node.shouldSpawnArrival(Integer.MAX_VALUE));
assertFalse(node.shouldSpawnArrival(-1));
assertEquals(1.0, node.getServiceTime(null), DELTA);
assertEquals(1.0, node.getPositiveSample(null), DELTA);
node = ServerNode.createSource("Source", const1);
assertEquals("Source", node.name);
@@ -67,7 +67,7 @@ public class TestSimulation {
assertTrue(node.shouldSpawnArrival(Integer.MAX_VALUE - 1));
assertFalse(node.shouldSpawnArrival(Integer.MAX_VALUE));
assertTrue(node.shouldSpawnArrival(-1));
assertEquals(1.0, node.getServiceTime(null), DELTA);
assertEquals(1.0, node.getPositiveSample(null), DELTA);
node = ServerNode.createLimitedSource("Source", const1, 50);
assertEquals("Source", node.name);
@@ -78,28 +78,25 @@ public class TestSimulation {
assertFalse(node.shouldSpawnArrival(1000));
assertFalse(node.shouldSpawnArrival(Integer.MAX_VALUE));
assertTrue(node.shouldSpawnArrival(-1));
assertEquals(1.0, node.getServiceTime(null), DELTA);
assertEquals(1.0, node.getPositiveSample(null), DELTA);
}
@Test
public void event() {
var node = ServerNode.createSource("Source", const0);
var event = Event.newUnavailable(node, 0, 1);
var event = Event.newType(node, 0, Event.Type.ARRIVAL);
assertEquals(node, event.node);
assertEquals(0.0, event.started, 0.000000000001);
assertEquals(1.0, event.time, 0.000000000001);
assertEquals(Event.Type.UNAVAILABLE, event.type);
assertEquals(0.0, event.time, 0.000000000001);
assertEquals(Event.Type.ARRIVAL, event.type);
var event2 = Event.newArrival(node, 1.0, 5.0);
var event2 = Event.newArrival(node, 1.0);
assertEquals(node, event2.node);
assertEquals(1.0, event2.started, 0.000000000001);
assertEquals(5.0, event2.time, 0.000000000001);
assertEquals(1.0, event2.time, 0.000000000001);
assertEquals(Event.Type.ARRIVAL, event2.type);
var event3 = Event.newDeparture(node, 7.0, 8.0);
var event3 = Event.newDeparture(node, 5.0);
assertEquals(node, event3.node);
assertEquals(7.0, event3.started, 0.000000000001);
assertEquals(8.0, event3.time, 0.000000000001);
assertEquals(5.0, event3.time, 0.000000000001);
assertEquals(Event.Type.DEPARTURE, event3.type);
assertEquals(0, event2.compareTo(event2));