/*
* The MIT License
*
* Copyright (c) 2004-2010, Sun Microsystems, Inc., Kohsuke Kawaguchi,
* Stephen Connolly, Tom Huybrechts, InfraDNA, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package hudson.model;
import hudson.AbortException;
import hudson.BulkChange;
import hudson.ExtensionList;
import hudson.ExtensionPoint;
import hudson.Util;
import hudson.XmlFile;
import hudson.init.Initializer;
import static hudson.init.InitMilestone.JOB_LOADED;
import static hudson.util.Iterators.reverse;
import hudson.cli.declarative.CLIMethod;
import hudson.cli.declarative.CLIResolver;
import hudson.model.queue.AbstractQueueTask;
import hudson.model.queue.Executables;
import hudson.model.queue.SubTask;
import hudson.model.queue.FutureImpl;
import hudson.model.queue.MappingWorksheet;
import hudson.model.queue.MappingWorksheet.Mapping;
import hudson.model.queue.QueueSorter;
import hudson.model.queue.QueueTaskDispatcher;
import hudson.model.queue.Tasks;
import hudson.model.queue.WorkUnit;
import hudson.model.Node.Mode;
import hudson.model.listeners.SaveableListener;
import hudson.model.queue.CauseOfBlockage;
import hudson.model.queue.FoldableAction;
import hudson.model.queue.CauseOfBlockage.BecauseLabelIsBusy;
import hudson.model.queue.CauseOfBlockage.BecauseNodeIsOffline;
import hudson.model.queue.CauseOfBlockage.BecauseLabelIsOffline;
import hudson.model.queue.CauseOfBlockage.BecauseNodeIsBusy;
import hudson.model.queue.WorkUnitContext;
import hudson.triggers.SafeTimerTask;
import hudson.triggers.Trigger;
import hudson.util.OneShotEvent;
import hudson.util.TimeUnit2;
import hudson.util.XStream2;
import hudson.util.ConsistentHash;
import hudson.util.ConsistentHash.Hash;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.lang.ref.WeakReference;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Calendar;
import java.util.Collection;
import java.util.Collections;
import java.util.GregorianCalendar;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.TreeSet;
import java.util.Map.Entry;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.Future;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.management.timer.Timer;
import javax.servlet.ServletException;
import org.kohsuke.stapler.HttpResponse;
import org.kohsuke.stapler.HttpResponses;
import org.kohsuke.stapler.export.Exported;
import org.kohsuke.stapler.export.ExportedBean;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.converters.basic.AbstractSingleValueConverter;
import java.util.HashSet;
/**
* Build queue.
*
* <p>
* This class implements the core scheduling logic. {@link Task} represents the executable
* task that are placed in the queue. While in the queue, it's wrapped into {@link Item}
* so that we can keep track of additional data used for deciding what to exeucte when.
*
* <p>
* Items in queue goes through several stages, as depicted below:
* <pre>
* (enter) --> waitingList --+--> blockedProjects
* | ^
* | |
* | v
* +--> buildables ---> pending ---> (executed)
* </pre>
*
* <p>
* In addition, at any stage, an item can be removed from the queue (for example, when the user
* cancels a job in the queue.) See the corresponding field for their exact meanings.
*
* @author Kohsuke Kawaguchi
*/
@ExportedBean
public class Queue extends ResourceController implements Saveable {
/**
* Items that are waiting for its quiet period to pass.
*
* <p>
* This consists of {@link Item}s that cannot be run yet
* because its time has not yet come.
*/
private final Set<WaitingItem> waitingList = new TreeSet<WaitingItem>();
/**
* {@link Task}s that can be built immediately
* but blocked because another build is in progress,
* required {@link Resource}s are not available, or otherwise blocked
* by {@link Task#isBuildBlocked()}.
*/
private final ItemList<BlockedItem> blockedProjects = new ItemList<BlockedItem>();
/**
* {@link Task}s that can be built immediately
* that are waiting for available {@link Executor}.
* This list is sorted in such a way that earlier items are built earlier.
*/
private final ItemList<BuildableItem> buildables = new ItemList<BuildableItem>();
/**
* {@link Task}s that are being handed over to the executor, but execution
* has not started yet.
*/
private final ItemList<BuildableItem> pendings = new ItemList<BuildableItem>();
/**
* Data structure created for each idle {@link Executor}.
* This is a job offer from the queue to an executor.
*
* <p>
* An idle executor (that calls {@link Queue#pop()} creates
* a new {@link JobOffer} and gets itself {@linkplain Queue#parked parked},
* and we'll eventually hand out an {@link #workUnit} to build.
*/
public class JobOffer extends MappingWorksheet.ExecutorSlot {
public final Executor executor;
/**
* Used to wake up an executor, when it has an offered
* {@link Project} to build.
*/
private final OneShotEvent event = new OneShotEvent(Queue.this);
/**
* The work unit that this {@link Executor} is going to handle.
* (Or null, in which case event is used to trigger a queue maintenance.)
*/
private WorkUnit workUnit;
private JobOffer(Executor executor) {
this.executor = executor;
}
@Override
protected void set(WorkUnit p) {
assert this.workUnit == null;
this.workUnit = p;
event.signal();
}
@Override
public Executor getExecutor() {
return executor;
}
/**
* Verifies that the {@link Executor} represented by this object is capable of executing the given task.
*/
public boolean canTake(Task task) {
Node node = getNode();
if (node==null) return false; // this executor is about to die
if(node.canTake(task)!=null)
return false; // this node is not able to take the task
for (QueueTaskDispatcher d : QueueTaskDispatcher.all())
if (d.canTake(node,task)!=null)
return false;
return isAvailable();
}
/**
* Is this executor ready to accept some tasks?
*/
public boolean isAvailable() {
return workUnit == null && !executor.getOwner().isOffline() && executor.getOwner().isAcceptingTasks();
}
public Node getNode() {
return executor.getOwner().getNode();
}
public boolean isNotExclusive() {
return getNode().getMode() == Mode.NORMAL;
}
}
/**
* The executors that are currently waiting for a job to run.
*/
private final Map<Executor,JobOffer> parked = new HashMap<Executor,JobOffer>();
private volatile transient LoadBalancer loadBalancer;
private volatile transient QueueSorter sorter;
public Queue(LoadBalancer loadBalancer) {
this.loadBalancer = loadBalancer.sanitize();
// if all the executors are busy doing something, then the queue won't be maintained in
// timely fashion, so use another thread to make sure it happens.
new MaintainTask(this);
}
public LoadBalancer getLoadBalancer() {
return loadBalancer;
}
public void setLoadBalancer(LoadBalancer loadBalancer) {
if(loadBalancer==null) throw new IllegalArgumentException();
this.loadBalancer = loadBalancer;
}
public QueueSorter getSorter() {
return sorter;
}
public void setSorter(QueueSorter sorter) {
this.sorter = sorter;
}
/**
* Loads the queue contents that was {@link #save() saved}.
*/
public synchronized void load() {
try {
// first try the old format
File queueFile = getQueueFile();
if (queueFile.exists()) {
BufferedReader in = new BufferedReader(new InputStreamReader(new FileInputStream(queueFile)));
String line;
while ((line = in.readLine()) != null) {
AbstractProject j = Hudson.getInstance().getItemByFullName(line, AbstractProject.class);
if (j != null)
j.scheduleBuild();
}
in.close();
// discard the queue file now that we are done
queueFile.delete();
} else {
queueFile = getXMLQueueFile();
if (queueFile.exists()) {
List list = (List) new XmlFile(XSTREAM, queueFile).read();
int maxId = 0;
for (Object o : list) {
if (o instanceof Task) {
// backward compatibility
schedule((Task)o, 0);
} else if (o instanceof Item) {
Item item = (Item)o;
if(item.task==null)
continue; // botched persistence. throw this one away
maxId = Math.max(maxId, item.id);
if (item instanceof WaitingItem) {
waitingList.add((WaitingItem) item);
} else if (item instanceof BlockedItem) {
blockedProjects.put(item.task, (BlockedItem) item);
} else if (item instanceof BuildableItem) {
buildables.add((BuildableItem) item);
} else {
throw new IllegalStateException("Unknown item type! " + item);
}
} // this conveniently ignores null
}
WaitingItem.COUNTER.set(maxId);
// I just had an incident where all the executors are dead at AbstractProject._getRuns()
// because runs is null. Debugger revealed that this is caused by a MatrixConfiguration
// object that doesn't appear to be de-serialized properly.
// I don't know how this problem happened, but to diagnose this problem better
// when it happens again, save the old queue file for introspection.
File bk = new File(queueFile.getPath() + ".bak");
bk.delete();
queueFile.renameTo(bk);
queueFile.delete();
}
}
} catch (IOException e) {
LOGGER.log(Level.WARNING, "Failed to load the queue file " + getXMLQueueFile(), e);
}
}
/**
* Persists the queue contents to the disk.
*/
public synchronized void save() {
if(BulkChange.contains(this)) return;
// write out the tasks on the queue
ArrayList<Queue.Item> items = new ArrayList<Queue.Item>();
for (Item item: getItems()) {
if(item.task instanceof TransientTask) continue;
items.add(item);
}
try {
XmlFile queueFile = new XmlFile(XSTREAM, getXMLQueueFile());
queueFile.write(items);
SaveableListener.fireOnChange(this, queueFile);
} catch (IOException e) {
LOGGER.log(Level.WARNING, "Failed to write out the queue file " + getXMLQueueFile(), e);
}
}
/**
* Wipes out all the items currently in the queue, as if all of them are cancelled at once.
*/
@CLIMethod(name="clear-queue")
public synchronized void clear() {
Hudson.getInstance().checkPermission(Hudson.ADMINISTER);
for (WaitingItem i : waitingList)
i.onCancelled();
waitingList.clear();
blockedProjects.cancelAll();
buildables.cancelAll();
scheduleMaintenance();
}
/**
* Called from queue.jelly.
*/
public HttpResponse doClearQueue() throws IOException, ServletException {
Hudson.getInstance().getQueue().clear();
return HttpResponses.forwardToPreviousPage();
}
private File getQueueFile() {
return new File(Hudson.getInstance().getRootDir(), "queue.txt");
}
/*package*/ File getXMLQueueFile() {
return new File(Hudson.getInstance().getRootDir(), "queue.xml");
}
/**
* @deprecated as of 1.311
* Use {@link #schedule(AbstractProject)}
*/
public boolean add(AbstractProject p) {
return schedule(p)!=null;
}
/**
* Schedule a new build for this project.
*
* @return true if the project is actually added to the queue.
* false if the queue contained it and therefore the add()
* was noop
*/
public WaitingItem schedule(AbstractProject p) {
return schedule(p, p.getQuietPeriod());
}
/**
* Schedules a new build with a custom quiet period.
*
* <p>
* Left for backward compatibility with <1.114.
*
* @since 1.105
* @deprecated as of 1.311
* Use {@link #schedule(Task, int)}
*/
public boolean add(AbstractProject p, int quietPeriod) {
return schedule(p, quietPeriod)!=null;
}
/**
* Schedules an execution of a task.
*
* @param actions
* These actions can be used for associating information scoped to a particular build, to
* the task being queued. Upon the start of the build, these {@link Action}s will be automatically
* added to the {@link Run} object, and hence avaialable to everyone.
* For the convenience of the caller, this list can contain null, and those will be silently ignored.
* @since 1.311
* @return
* null if this task is already in the queue and therefore the add operation was no-op.
* Otherwise indicates the {@link WaitingItem} object added, although the nature of the queue
* is that such {@link Item} only captures the state of the item at a particular moment,
* and by the time you inspect the object, some of its information can be already stale.
*
* That said, one can still look at {@link WaitingItem#future}, {@link WaitingItem#id}, etc.
*/
public synchronized WaitingItem schedule(Task p, int quietPeriod, List<Action> actions) {
// remove nulls
actions = new ArrayList<Action>(actions);
for (Iterator<Action> itr = actions.iterator(); itr.hasNext();) {
Action a = itr.next();
if (a==null) itr.remove();
}
for(QueueDecisionHandler h : QueueDecisionHandler.all())
if (!h.shouldSchedule(p, actions))
return null; // veto
return scheduleInternal(p, quietPeriod, actions);
}
/**
* Schedules an execution of a task.
*
* @since 1.311
* @return
* null if this task is already in the queue and therefore the add operation was no-op.
* Otherwise indicates the {@link WaitingItem} object added, although the nature of the queue
* is that such {@link Item} only captures the state of the item at a particular moment,
* and by the time you inspect the object, some of its information can be already stale.
*
* That said, one can still look at {@link WaitingItem#future}, {@link WaitingItem#id}, etc.
*/
private synchronized WaitingItem scheduleInternal(Task p, int quietPeriod, List<Action> actions) {
Calendar due = new GregorianCalendar();
due.add(Calendar.SECOND, quietPeriod);
// Do we already have this task in the queue? Because if so, we won't schedule a new one.
List<Item> duplicatesInQueue = new ArrayList<Item>();
for(Item item : getItems(p)) {
boolean shouldScheduleItem = false;
for (QueueAction action: item.getActions(QueueAction.class)) {
shouldScheduleItem |= action.shouldSchedule(actions);
}
for (QueueAction action: Util.filter(actions,QueueAction.class)) {
shouldScheduleItem |= action.shouldSchedule(item.getActions());
}
if(!shouldScheduleItem) {
duplicatesInQueue.add(item);
}
}
if (duplicatesInQueue.isEmpty()) {
LOGGER.fine(p.getFullDisplayName() + " added to queue");
// put the item in the queue
WaitingItem added = new WaitingItem(due,p,actions);
waitingList.add(added);
scheduleMaintenance(); // let an executor know that a new item is in the queue.
return added;
}
LOGGER.fine(p.getFullDisplayName() + " is already in the queue");
// but let the actions affect the existing stuff.
for(Item item : duplicatesInQueue) {
for(FoldableAction a : Util.filter(actions,FoldableAction.class)) {
a.foldIntoExisting(item, p, actions);
}
}
boolean queueUpdated = false;
for(WaitingItem wi : Util.filter(duplicatesInQueue,WaitingItem.class)) {
if(quietPeriod<=0) {
// the user really wants to build now, and they mean NOW.
// so let's pull in the timestamp if we can.
if (wi.timestamp.before(due))
continue;
} else {
// otherwise we do the normal quiet period implementation
if (wi.timestamp.after(due))
continue;
// quiet period timer reset. start the period over again
}
// waitingList is sorted, so when we change a timestamp we need to maintain order
waitingList.remove(wi);
wi.timestamp = due;
waitingList.add(wi);
queueUpdated=true;
}
if (queueUpdated) scheduleMaintenance();
return null;
}
/**
* @deprecated as of 1.311
* Use {@link #schedule(Task, int)}
*/
public synchronized boolean add(Task p, int quietPeriod) {
return schedule(p, quietPeriod)!=null;
}
public synchronized WaitingItem schedule(Task p, int quietPeriod) {
return schedule(p, quietPeriod, new Action[0]);
}
/**
* @deprecated as of 1.311
* Use {@link #schedule(Task, int, Action...)}
*/
public synchronized boolean add(Task p, int quietPeriod, Action... actions) {
return schedule(p, quietPeriod, actions)!=null;
}
/**
* Convenience wrapper method around {@link #schedule(Task, int, List)}
*/
public synchronized WaitingItem schedule(Task p, int quietPeriod, Action... actions) {
return schedule(p, quietPeriod, Arrays.asList(actions));
}
/**
* Cancels the item in the queue. If the item is scheduled more than once, cancels the first occurrence.
*
* @return true if the project was indeed in the queue and was removed.
* false if this was no-op.
*/
public synchronized boolean cancel(Task p) {
LOGGER.fine("Cancelling " + p.getFullDisplayName());
for (Iterator<WaitingItem> itr = waitingList.iterator(); itr.hasNext();) {
Item item = itr.next();
if (item.task.equals(p)) {
itr.remove();
item.onCancelled();
return true;
}
}
// use bitwise-OR to make sure that both branches get evaluated all the time
return blockedProjects.cancel(p)!=null | buildables.cancel(p)!=null;
}
public synchronized boolean cancel(Item item) {
LOGGER.fine("Cancelling " + item.task.getFullDisplayName() + " item#" + item.id);
// use bitwise-OR to make sure that all the branches get evaluated all the time
boolean r = (item instanceof WaitingItem && waitingList.remove(item)) | blockedProjects.remove(item) | buildables.remove(item);
if(r)
item.onCancelled();
return r;
}
public synchronized boolean isEmpty() {
return waitingList.isEmpty() && blockedProjects.isEmpty() && buildables.isEmpty() && pendings.isEmpty();
}
private synchronized WaitingItem peek() {
return waitingList.iterator().next();
}
/**
* Gets a snapshot of items in the queue.
*
* Generally speaking the array is sorted such that the items that are most likely built sooner are
* at the end.
*/
@Exported(inline=true)
public synchronized Item[] getItems() {
Item[] r = new Item[waitingList.size() + blockedProjects.size() + buildables.size() + pendings.size()];
waitingList.toArray(r);
int idx = waitingList.size();
for (BlockedItem p : blockedProjects.values())
r[idx++] = p;
for (BuildableItem p : reverse(buildables.values()))
r[idx++] = p;
for (BuildableItem p : reverse(pendings.values()))
r[idx++] = p;
return r;
}
public synchronized Item getItem(int id) {
for (Item item: waitingList) if (item.id == id) return item;
for (Item item: blockedProjects) if (item.id == id) return item;
for (Item item: buildables) if (item.id == id) return item;
for (Item item: pendings) if (item.id == id) return item;
return null;
}
/**
* Gets all the {@link BuildableItem}s that are waiting for an executor in the given {@link Computer}.
*/
public synchronized List<BuildableItem> getBuildableItems(Computer c) {
List<BuildableItem> result = new ArrayList<BuildableItem>();
_getBuildableItems(c, buildables, result);
_getBuildableItems(c, pendings, result);
return result;
}
private void _getBuildableItems(Computer c, ItemList<BuildableItem> col, List<BuildableItem> result) {
Node node = c.getNode();
for (BuildableItem p : col.values()) {
if (node.canTake(p.task) == null)
result.add(p);
}
}
/**
* Gets the snapshot of all {@link BuildableItem}s.
*/
public synchronized List<BuildableItem> getBuildableItems() {
ArrayList<BuildableItem> r = new ArrayList<BuildableItem>(buildables.values());
r.addAll(pendings.values());
return r;
}
/**
* Gets the snapshot of all {@link BuildableItem}s.
*/
public synchronized List<BuildableItem> getPendingItems() {
return new ArrayList<BuildableItem>(pendings.values());
}
synchronized Set<Task> getUnblockedQueuedTasks() {
Set<Task> unblockedQueuedTasks = new HashSet<Task>();
for (Item item: waitingList) {
unblockedQueuedTasks.add(item.task);
}
for (Item item: pendings) {
unblockedQueuedTasks.add(item.task);
}
for (Item item: buildables) {
unblockedQueuedTasks.add(item.task);
}
return unblockedQueuedTasks;
}
/**
* Is the given task currently pending execution?
*/
public synchronized boolean isPending(Task t) {
for (BuildableItem i : pendings)
if (i.task.equals(t))
return true;
return false;
}
/**
* How many {@link BuildableItem}s are assigned for the given label?
*/
public synchronized int countBuildableItemsFor(Label l) {
int r = 0;
for (BuildableItem bi : buildables.values())
if(bi.task.getAssignedLabel()==l)
r++;
for (BuildableItem bi : pendings.values())
if(bi.task.getAssignedLabel()==l)
r++;
return r;
}
/**
* Gets the information about the queue item for the given project.
*
* @return null if the project is not in the queue.
*/
public synchronized Item getItem(Task t) {
BlockedItem bp = blockedProjects.get(t);
if (bp!=null)
return bp;
BuildableItem bi = buildables.get(t);
if(bi!=null)
return bi;
bi = pendings.get(t);
if(bi!=null)
return bi;
for (Item item : waitingList) {
if (item.task == t)
return item;
}
return null;
}
/**
* Gets the information about the queue item for the given project.
*
* @return null if the project is not in the queue.
*/
public synchronized List<Item> getItems(Task t) {
List<Item> result =new ArrayList<Item>();
result.addAll(blockedProjects.getAll(t));
result.addAll(buildables.getAll(t));
result.addAll(pendings.getAll(t));
for (Item item : waitingList) {
if (item.task == t)
result.add(item);
}
return result;
}
/**
* Left for backward compatibility.
*
* @see #getItem(Task)
public synchronized Item getItem(AbstractProject p) {
return getItem((Task) p);
}
*/
/**
* Returns true if this queue contains the said project.
*/
public synchronized boolean contains(Task t) {
if (blockedProjects.containsKey(t) || buildables.containsKey(t) || pendings.containsKey(t))
return true;
for (Item item : waitingList) {
if (item.task == t)
return true;
}
return false;
}
/**
* Called by the executor to fetch something to build next.
* <p>
* This method blocks until a next project becomes buildable.
*/
public synchronized WorkUnit pop() throws InterruptedException {
final Executor exec = Executor.currentExecutor();
if (exec instanceof OneOffExecutor) {
OneOffExecutor ooe = (OneOffExecutor) exec;
final WorkUnit wu = ooe.getWorkUnit();
pendings.remove(wu.context.item);
return wu;
}
try {
while (true) {
final JobOffer offer = new JobOffer(exec);
long sleep = -1;
// consider myself parked
assert !parked.containsKey(exec);
parked.put(exec, offer);
// reuse executor thread to do a queue maintenance.
// at the end of this we get all the buildable jobs
// in the buildables field.
maintain();
// allocate buildable jobs to executors
Iterator<BuildableItem> itr = buildables.iterator();
while (itr.hasNext()) {
BuildableItem p = itr.next();
// one last check to make sure this build is not blocked.
if (isBuildBlocked(p.task)) {
itr.remove();
blockedProjects.put(p.task,new BlockedItem(p));
continue;
}
List<JobOffer> candidates = new ArrayList<JobOffer>(parked.size());
for (JobOffer j : parked.values())
if(j.canTake(p.task))
candidates.add(j);
MappingWorksheet ws = new MappingWorksheet(p, candidates);
Mapping m = loadBalancer.map(p.task, ws);
if (m == null)
// if we couldn't find the executor that fits,
// just leave it in the buildables list and
// check if we can execute other projects
continue;
// found a matching executor. use it.
WorkUnitContext wuc = new WorkUnitContext(p);
m.execute(wuc);
itr.remove();
if (!wuc.getWorkUnits().isEmpty())
pendings.add(p);
}
// we went over all the buildable projects and awaken
// all the executors that got work to do. now, go to sleep
// until this thread is awakened. If this executor assigned a job to
// itself above, the block method will return immediately.
if (!waitingList.isEmpty()) {
// wait until the first item in the queue is due
sleep = peek().timestamp.getTimeInMillis() - new GregorianCalendar().getTimeInMillis();
if (sleep < 100) sleep = 100; // avoid wait(0)
}
if (sleep == -1)
offer.event.block();
else
offer.event.block(sleep);
// retract the offer object
assert parked.get(exec) == offer;
parked.remove(exec);
// am I woken up because I have a project to build?
if (offer.workUnit != null) {
// if so, just build it
LOGGER.fine("Pop returning " + offer.workUnit + " for " + exec.getName());
// TODO: I think this has to be done by the last executor that leaves the pop(), not by main executor
if (offer.workUnit.isMainWork())
pendings.remove(offer.workUnit.context.item);
return offer.workUnit;
}
// otherwise run a queue maintenance
}
} finally {
// remove myself from the parked list
JobOffer offer = parked.remove(exec);
if (offer != null && offer.workUnit != null) {
// we are already assigned a project, but now we can't handle it.
offer.workUnit.context.abort(new AbortException());
}
// since this executor might have been chosen for
// maintenance, schedule another one. Worst case
// we'll just run a pointless maintenance, and that's
// fine.
scheduleMaintenance();
}
}
/**
* Checks the queue and runs anything that can be run.
*
* <p>
* When conditions are changed, this method should be invoked.
* <p>
* This wakes up one {@link Executor} so that it will maintain a queue.
*/
public synchronized void scheduleMaintenance() {
// this code assumes that after this method is called
// no more executors will be offered job except by
// the pop() code.
for (Entry<Executor, JobOffer> av : parked.entrySet()) {
if (av.getValue().workUnit == null) {
av.getValue().event.signal();
return;
}
}
}
/**
* Checks if the given task is blocked.
*/
private boolean isBuildBlocked(Task t) {
return t.isBuildBlocked() || !canRun(t.getResourceList());
}
/**
* Make sure we don't queue two tasks of the same project to be built
* unless that project allows concurrent builds.
*/
private boolean allowNewBuildableTask(Task t) {
try {
if (t.isConcurrentBuild())
return true;
} catch (AbstractMethodError e) {
// earlier versions don't have the "isConcurrentBuild" method, so fall back gracefully
}
return !buildables.containsKey(t) && !pendings.containsKey(t);
}
/**
* Queue maintenance.
* <p>
* Move projects between {@link #waitingList}, {@link #blockedProjects}, and {@link #buildables}
* appropriately.
*/
public synchronized void maintain() {
if (LOGGER.isLoggable(Level.FINE))
LOGGER.fine("Queue maintenance started " + this);
// blocked -> buildable
Iterator<BlockedItem> itr = blockedProjects.values().iterator();
while (itr.hasNext()) {
BlockedItem p = itr.next();
if (!isBuildBlocked(p.task) && allowNewBuildableTask(p.task)) {
// ready to be executed
LOGGER.fine(p.task.getFullDisplayName() + " no longer blocked");
itr.remove();
makeBuildable(new BuildableItem(p));
}
}
while (!waitingList.isEmpty()) {
WaitingItem top = peek();
if (!top.timestamp.before(new GregorianCalendar()))
return; // finished moving all ready items from queue
waitingList.remove(top);
Task p = top.task;
if (!isBuildBlocked(p) && allowNewBuildableTask(p)) {
// ready to be executed immediately
LOGGER.fine(p.getFullDisplayName() + " ready to build");
makeBuildable(new BuildableItem(top));
} else {
// this can't be built now because another build is in progress
// set this project aside.
LOGGER.fine(p.getFullDisplayName() + " is blocked");
blockedProjects.put(p,new BlockedItem(top));
}
}
final QueueSorter s = sorter;
if (s != null)
s.sortBuildableItems(buildables);
}
private void makeBuildable(BuildableItem p) {
if(Hudson.FLYWEIGHT_SUPPORT && p.task instanceof FlyweightTask && !ifBlockedByHudsonShutdown(p.task)) {
ConsistentHash<Node> hash = new ConsistentHash<Node>(new Hash<Node>() {
public String hash(Node node) {
return node.getNodeName();
}
});
Hudson h = Hudson.getInstance();
hash.add(h, h.getNumExecutors()*100);
for (Node n : h.getNodes())
hash.add(n,n.getNumExecutors()*100);
Label lbl = p.task.getAssignedLabel();
for (Node n : hash.list(p.task.getFullDisplayName())) {
Computer c = n.toComputer();
if (c==null || c.isOffline()) continue;
if (lbl!=null && !lbl.contains(n)) continue;
c.startFlyWeightTask(new WorkUnitContext(p).createWorkUnit(p.task));
pendings.add(p);
return;
}
// if the execution get here, it means we couldn't schedule it anywhere.
// so do the scheduling like other normal jobs.
}
buildables.put(p.task,p);
}
public static boolean ifBlockedByHudsonShutdown(Task task) {
return Hudson.getInstance().isQuietingDown() && !(task instanceof NonBlockingTask);
}
public Api getApi() {
return new Api(this);
}
/**
* Marks {@link Task}s that are not persisted.
* @since 1.311
*/
public interface TransientTask extends Task {}
/**
* Marks {@link Task}s that do not consume {@link Executor}.
* @see OneOffExecutor
* @since 1.318
*/
public interface FlyweightTask extends Task {}
/**
* Marks {@link Task}s that are not affected by the {@linkplain Hudson#isQuietingDown()} quieting down},
* because these tasks keep other tasks executing.
*
* @since 1.336
*/
public interface NonBlockingTask extends Task {}
/**
* Task whose execution is controlled by the queue.
*
* <p>
* {@link #equals(Object) Value equality} of {@link Task}s is used
* to collapse two tasks into one. This is used to avoid infinite
* queue backlog.
*
* <p>
* Pending {@link Task}s are persisted when Hudson shuts down, so
* it needs to be persistable via XStream. To create a non-persisted
* transient Task, extend {@link TransientTask} marker interface.
*
* <p>
* Plugins are encouraged to extend from {@link AbstractQueueTask}
* instead of implementing this interface directly, to maintain
* compatibility with future changes to this interface.
*
* <p>
* For historical reasons, {@link Task} object by itself
* also represents the "primary" sub-task (and as implied by this
* design, a {@link Task} must have at least one sub-task.)
* Most of the time, the primary subtask is the only sub task.
*/
public interface Task extends ModelObject, SubTask {
/**
* Returns true if the execution should be blocked
* for temporary reasons.
*
* <p>
* Short-hand for {@code getCauseOfBlockage()!=null}.
*/
boolean isBuildBlocked();
/**
* @deprecated as of 1.330
* Use {@link CauseOfBlockage#getShortDescription()} instead.
*/
String getWhyBlocked();
/**
* If the execution of this task should be blocked for temporary reasons,
* this method returns a non-null object explaining why.
*
* <p>
* Otherwise this method returns null, indicating that the build can proceed right away.
*
* <p>
* This can be used to define mutual exclusion that goes beyond
* {@link #getResourceList()}.
*/
CauseOfBlockage getCauseOfBlockage();
/**
* Unique name of this task.
*
* <p>
* This method is no longer used, left here for compatibility. Just return {@link #getDisplayName()}.
*/
String getName();
/**
* @see hudson.model.Item#getFullDisplayName()
*/
String getFullDisplayName();
/**
* Checks the permission to see if the current user can abort this executable.
* Returns normally from this method if it's OK.
*
* @throws org.acegisecurity.AccessDeniedException if the permission is not granted.
*/
void checkAbortPermission();
/**
* Works just like {@link #checkAbortPermission()} except it indicates the status by a return value,
* instead of exception.
*/
boolean hasAbortPermission();
/**
* Returns the URL of this task relative to the context root of the application.
*
* <p>
* When the user clicks an item in the queue, this is the page where the user is taken to.
* Hudson expects the current instance to be bound to the URL returned by this method.
*
* @return
* URL that ends with '/'.
*/
String getUrl();
/**
* True if the task allows concurrent builds
*
* @since 1.338
*/
boolean isConcurrentBuild();
/**
* Obtains the {@link SubTask}s that constitute this task.
*
* <p>
* The collection returned by this method must also contain the primary {@link SubTask}
* represented by this {@link Task} object itself as the first element.
* The returned value is read-only.
*
* <p>
* At least size 1.
*
* <p>
* Since this is a newly added method, the invocation may results in {@link AbstractMethodError}.
* Use {@link Tasks#getSubTasksOf(Task)} that avoids this.
*
* @since 1.377
*/
Collection<? extends SubTask> getSubTasks();
}
/**
* Represents the real meat of the computation run by {@link Executor}.
*
* <h2>Views</h2>
* <p>
* Implementation must have <tt>executorCell.jelly</tt>, which is
* used to render the HTML that indicates this executable is executing.
*/
public interface Executable extends Runnable {
/**
* Task from which this executable was created.
* Never null.
*
* <p>
* Since this method went through a signature change in 1.377, the invocation may results in
* {@link AbstractMethodError}.
* Use {@link Executables#getParentOf(Executable)} that avoids this.
*/
SubTask getParent();
/**
* Called by {@link Executor} to perform the task
*/
void run();
/**
* Estimate of how long will it take to execute this executable.
* Measured in milliseconds.
*
* Please, consider using {@link Executables#getEstimatedDurationFor(Executable)}
* to protected against AbstractMethodErrors!
*
* @return -1 if it's impossible to estimate.
* @since 1.383
*/
long getEstimatedDuration();
/**
* Used to render the HTML. Should be a human readable text of what this executable is.
*/
@Override String toString();
}
/**
* Item in a queue.
*/
@ExportedBean(defaultVisibility = 999)
public static abstract class Item extends Actionable {
/**
* VM-wide unique ID that tracks the {@link Task} as it moves through different stages
* in the queue (each represented by different subtypes of {@link Item}.
*/
//TODO: review and check whether we can do it private
public final int id;
/**
* Project to be built.
*/
//TODO: review and check whether we can do it private
@Exported
public final Task task;
private /*almost final*/ transient FutureImpl future;
/**
* Build is blocked because another build is in progress,
* required {@link Resource}s are not available, or otherwise blocked
* by {@link Task#isBuildBlocked()}.
*/
@Exported
public boolean isBlocked() { return this instanceof BlockedItem; }
/**
* Build is waiting the executor to become available.
* This flag is only used in {@link Queue#getItems()} for
* 'pseudo' items that are actually not really in the queue.
*/
@Exported
public boolean isBuildable() { return this instanceof BuildableItem; }
/**
* True if the item is starving for an executor for too long.
*/
@Exported
public boolean isStuck() { return false; }
/**
* Can be used to wait for the completion (either normal, abnormal, or cancellation) of the {@link Task}.
* <p>
* Just like {@link #id}, the same object tracks various stages of the queue.
*/
public Future<Executable> getFuture() { return future; }
/**
* Convenience method that returns a read only view of the {@link Cause}s associated with this item in the queue.
*
* @return can be empty but never null
* @since 1.343
*/
public final List<Cause> getCauses() {
CauseAction ca = getAction(CauseAction.class);
if (ca!=null)
return Collections.unmodifiableList(ca.getCauses());
return Collections.emptyList();
}
protected Item(Task task, List<Action> actions, int id, FutureImpl future) {
this.task = task;
this.id = id;
this.future = future;
for (Action action: actions) addAction(action);
}
protected Item(Item item) {
this(item.task, item.getActions(), item.id, item.future);
}
public int getId() {
return id;
}
public Task getTask() {
return task;
}
/**
* Gets a human-readable status message describing why it's in the queue.
*/
@Exported
public final String getWhy() {
CauseOfBlockage cob = getCauseOfBlockage();
return cob!=null ? cob.getShortDescription() : null;
}
/**
* Gets an object that describes why this item is in the queue.
*/
//TODO: review and check whether we can do it private
public abstract CauseOfBlockage getCauseOfBlockage();
/**
* Gets a human-readable message about the parameters of this item
* @return String
*/
@Exported
public String getParams() {
StringBuilder s = new StringBuilder();
for(Action action : getActions()) {
if(action instanceof ParametersAction) {
ParametersAction pa = (ParametersAction)action;
for (ParameterValue p : pa.getParameters()) {
s.append('\n').append(p.getShortDescription());
}
}
}
return s.toString();
}
public boolean hasCancelPermission() {
return task.hasAbortPermission();
}
public String getDisplayName() {
// TODO Auto-generated method stub
return null;
}
public String getSearchUrl() {
// TODO Auto-generated method stub
return null;
}
/**
* Called from queue.jelly.
*/
public HttpResponse doCancelQueue() throws IOException, ServletException {
Hudson.getInstance().getQueue().cancel(this);
return HttpResponses.forwardToPreviousPage();
}
/**
* Participates in the cancellation logic to set the {@link #future} accordingly.
*/
/*package*/ void onCancelled() {
future.setAsCancelled();
}
private Object readResolve() {
this.future = new FutureImpl(task);
return this;
}
@Override
public String toString() {
return getClass().getName()+':'+task.toString();
}
}
/**
* An optional interface for actions on Queue.Item.
* Lets the action cooperate in queue management.
*
* @since 1.300-ish.
*/
public interface QueueAction extends Action {
/**
* Returns whether the new item should be scheduled.
* An action should return true if the associated task is 'different enough' to warrant a separate execution.
*/
public boolean shouldSchedule(List<Action> actions);
}
/**
* Extension point for deciding if particular job should be scheduled or not.
*
* <p>
* This handler is consulted every time someone tries to submit a task to the queue.
* If any of the registered handlers returns false, the task will not be added
* to the queue, and the task will never get executed.
*
* <p>
* This extension point is still a subject to change, as we are seeking more
* comprehensive Queue pluggability. See HUDSON-2072.
*
* @since 1.316
*/
public static abstract class QueueDecisionHandler implements ExtensionPoint {
/**
* Returns whether the new item should be scheduled.
*/
public abstract boolean shouldSchedule(Task p, List<Action> actions);
/**
* All registered {@link QueueDecisionHandler}s
* @return
*/
public static ExtensionList<QueueDecisionHandler> all() {
return Hudson.getInstance().getExtensionList(QueueDecisionHandler.class);
}
}
/**
* {@link Item} in the {@link Queue#waitingList} stage.
*/
public static final class WaitingItem extends Item implements Comparable<WaitingItem> {
private static final AtomicInteger COUNTER = new AtomicInteger(0);
/**
* This item can be run after this time.
*/
//TODO: review and check whether we can do it private
@Exported
public Calendar timestamp;
public Calendar getTimestamp() {
return timestamp;
}
public WaitingItem(Calendar timestamp, Task project, List<Action> actions) {
super(project, actions, COUNTER.incrementAndGet(), new FutureImpl(project));
this.timestamp = timestamp;
}
public int compareTo(WaitingItem that) {
int r = this.timestamp.getTime().compareTo(that.timestamp.getTime());
if (r != 0) return r;
return this.id - that.id;
}
public CauseOfBlockage getCauseOfBlockage() {
long diff = timestamp.getTimeInMillis() - System.currentTimeMillis();
if (diff > 0)
return CauseOfBlockage.fromMessage(Messages._Queue_InQuietPeriod(Util.getTimeSpanString(diff)));
else
return CauseOfBlockage.fromMessage(Messages._Queue_Unknown());
}
}
/**
* Common part between {@link BlockedItem} and {@link BuildableItem}.
*/
public static abstract class NotWaitingItem extends Item {
/**
* When did this job exit the {@link Queue#waitingList} phase?
*/
@Exported
public final long buildableStartMilliseconds;
protected NotWaitingItem(WaitingItem wi) {
super(wi);
buildableStartMilliseconds = System.currentTimeMillis();
}
protected NotWaitingItem(NotWaitingItem ni) {
super(ni);
buildableStartMilliseconds = ni.buildableStartMilliseconds;
}
}
/**
* {@link Item} in the {@link Queue#blockedProjects} stage.
*/
public final class BlockedItem extends NotWaitingItem {
public BlockedItem(WaitingItem wi) {
super(wi);
}
public BlockedItem(NotWaitingItem ni) {
super(ni);
}
public CauseOfBlockage getCauseOfBlockage() {
ResourceActivity r = getBlockingActivity(task);
if (r != null) {
if (r == task) // blocked by itself, meaning another build is in progress
return CauseOfBlockage.fromMessage(Messages._Queue_InProgress());
return CauseOfBlockage.fromMessage(Messages._Queue_BlockedBy(r.getDisplayName()));
}
return task.getCauseOfBlockage();
}
}
/**
* {@link Item} in the {@link Queue#buildables} stage.
*/
public final static class BuildableItem extends NotWaitingItem {
public BuildableItem(WaitingItem wi) {
super(wi);
}
public BuildableItem(NotWaitingItem ni) {
super(ni);
}
public CauseOfBlockage getCauseOfBlockage() {
Hudson hudson = Hudson.getInstance();
if(ifBlockedByHudsonShutdown(task))
return CauseOfBlockage.fromMessage(Messages._Queue_HudsonIsAboutToShutDown());
Label label = task.getAssignedLabel();
if (hudson.getNodes().isEmpty())
label = null; // no master/slave. pointless to talk about nodes
if (label != null) {
if (label.isOffline()) {
Set<Node> nodes = label.getNodes();
if (nodes.size() != 1) return new BecauseLabelIsOffline(label);
else return new BecauseNodeIsOffline(nodes.iterator().next());
}
}
if(label==null)
return CauseOfBlockage.fromMessage(Messages._Queue_WaitingForNextAvailableExecutor());
Set<Node> nodes = label.getNodes();
if (nodes.size() != 1) return new BecauseLabelIsBusy(label);
else return new BecauseNodeIsBusy(nodes.iterator().next());
}
@Override
public boolean isStuck() {
Label label = task.getAssignedLabel();
if(label!=null && label.isOffline())
// no executor online to process this job. definitely stuck.
return true;
long d = task.getEstimatedDuration();
long elapsed = System.currentTimeMillis()-buildableStartMilliseconds;
if(d>=0) {
// if we were running elsewhere, we would have done this build ten times.
return elapsed > Math.max(d,60000L)*10;
} else {
// more than a day in the queue
return TimeUnit2.MILLISECONDS.toHours(elapsed)>24;
}
}
}
private static final Logger LOGGER = Logger.getLogger(Queue.class.getName());
/**
* This {@link XStream} instance is used to persist {@link Task}s.
*/
public static final XStream XSTREAM = new XStream2();
static {
XSTREAM.registerConverter(new AbstractSingleValueConverter() {
@Override
@SuppressWarnings("unchecked")
public boolean canConvert(Class klazz) {
return hudson.model.Item.class.isAssignableFrom(klazz);
}
@Override
public Object fromString(String string) {
Object item = Hudson.getInstance().getItemByFullName(string);
if(item==null) throw new NoSuchElementException("No such job exists: "+string);
return item;
}
@Override
public String toString(Object item) {
return ((hudson.model.Item) item).getFullName();
}
});
XSTREAM.registerConverter(new AbstractSingleValueConverter() {
@SuppressWarnings("unchecked")
@Override
public boolean canConvert(Class klazz) {
return Run.class.isAssignableFrom(klazz);
}
@Override
public Object fromString(String string) {
String[] split = string.split("#");
String projectName = split[0];
int buildNumber = Integer.parseInt(split[1]);
Job<?,?> job = (Job<?,?>) Hudson.getInstance().getItemByFullName(projectName);
if(job==null) throw new NoSuchElementException("No such job exists: "+projectName);
Run<?,?> run = job.getBuildByNumber(buildNumber);
if(run==null) throw new NoSuchElementException("No such build: "+string);
return run;
}
@Override
public String toString(Object object) {
Run<?,?> run = (Run<?,?>) object;
return run.getParent().getFullName() + "#" + run.getNumber();
}
});
}
/**
* Regularly invokes {@link Queue#maintain()} and clean itself up when
* {@link Queue} gets GC-ed.
*/
private static class MaintainTask extends SafeTimerTask {
private final WeakReference<Queue> queue;
MaintainTask(Queue queue) {
this.queue = new WeakReference<Queue>(queue);
long interval = 5 * Timer.ONE_SECOND;
Trigger.timer.schedule(this, interval, interval);
}
protected void doRun() {
Queue q = queue.get();
if (q != null)
q.maintain();
else
cancel();
}
}
/**
* {@link ArrayList} of {@link Item} with more convenience methods.
*/
private static class ItemList<T extends Item> extends ArrayList<T> {
public T get(Task task) {
for (T item: this) {
if (item.task == task) {
return item;
}
}
return null;
}
public List<T> getAll(Task task) {
List<T> result = new ArrayList<T>();
for (T item: this) {
if (item.task == task) {
result.add(item);
}
}
return result;
}
public boolean containsKey(Task task) {
return get(task) != null;
}
public T remove(Task task) {
Iterator<T> it = iterator();
while (it.hasNext()) {
T t = it.next();
if (t.task == task) {
it.remove();
return t;
}
}
return null;
}
public void put(Task task, T item) {
assert item.task == task;
add(item);
}
public ItemList<T> values() {
return this;
}
/**
* Works like {@link #remove(Task)} but also marks the {@link Item} as cancelled.
*/
public T cancel(Task p) {
T x = remove(p);
if(x!=null) x.onCancelled();
return x;
}
/**
* Works like {@link #remove(Object)} but also marks the {@link Item} as cancelled.
*/
public boolean cancel(Item t) {
boolean r = remove(t);
if(r) t.onCancelled();
return r;
}
public void cancelAll() {
for (T t : this)
t.onCancelled();
clear();
}
}
@CLIResolver
public static Queue getInstance() {
return Hudson.getInstance().getQueue();
}
/**
* Restores the queue content during the start up.
*/
@Initializer(after=JOB_LOADED)
public static void init(Hudson h) {
h.getQueue().load();
}
}