private boolean checkForConvergence() {
if (maxNumberOfIterations == currentIteration) {
if (log.isInfoEnabled()) {
log.info(
formatLogString(
"maximum number of iterations [" + currentIteration + "] reached, terminating..."));
}
return true;
}
if (convergenceAggregatorName != null) {
@SuppressWarnings("unchecked")
Aggregator<Value> aggregator = (Aggregator<Value>) aggregators.get(convergenceAggregatorName);
if (aggregator == null) {
throw new RuntimeException("Error: Aggregator for convergence criterion was null.");
}
Value aggregate = aggregator.getAggregate();
if (convergenceCriterion.isConverged(currentIteration, aggregate)) {
if (log.isInfoEnabled()) {
log.info(
formatLogString(
"convergence reached after ["
+ currentIteration
+ "] iterations, terminating..."));
}
return true;
}
}
return false;
}
private void onWorkerDoneEvent(WorkerDoneEvent workerDoneEvent) {
if (this.endOfSuperstep) {
throw new RuntimeException(
"Encountered WorderDoneEvent when still in End-of-Superstep status.");
}
workerDoneEventCounter++;
// if (log.isInfoEnabled()) {
// log.info("Sync event handler received WorkerDoneEvent event (" + workerDoneEventCounter +
// ")");
// }
String[] aggNames = workerDoneEvent.getAggregatorNames();
Value[] aggregates = workerDoneEvent.getAggregates(userCodeClassLoader);
if (aggNames.length != aggregates.length) {
throw new RuntimeException("Inconsistent WorkerDoneEvent received!");
}
for (int i = 0; i < aggNames.length; i++) {
@SuppressWarnings("unchecked")
Aggregator<Value> aggregator = (Aggregator<Value>) this.aggregators.get(aggNames[i]);
aggregator.aggregate(aggregates[i]);
}
if (workerDoneEventCounter % numberOfEventsUntilEndOfSuperstep == 0) {
endOfSuperstep = true;
Thread.currentThread().interrupt();
}
}
@Override
public void invoke() throws Exception {
userCodeClassLoader = LibraryCacheManager.getClassLoader(getEnvironment().getJobID());
TaskConfig taskConfig = new TaskConfig(getTaskConfiguration());
// store all aggregators
this.aggregators = new HashMap<String, Aggregator<?>>();
for (AggregatorWithName<?> aggWithName : taskConfig.getIterationAggregators()) {
aggregators.put(aggWithName.getName(), aggWithName.getAggregator());
}
// store the aggregator convergence criterion
if (taskConfig.usesConvergenceCriterion()) {
convergenceCriterion = taskConfig.getConvergenceCriterion();
convergenceAggregatorName = taskConfig.getConvergenceCriterionAggregatorName();
Preconditions.checkNotNull(convergenceAggregatorName);
}
maxNumberOfIterations = taskConfig.getNumberOfIterations();
// set up the event handler
int numEventsTillEndOfSuperstep = taskConfig.getNumberOfEventsUntilInterruptInIterativeGate(0);
eventHandler =
new SyncEventHandler(numEventsTillEndOfSuperstep, aggregators, userCodeClassLoader);
headEventReader.subscribeToEvent(eventHandler, WorkerDoneEvent.class);
IntegerRecord dummy = new IntegerRecord();
while (!terminationRequested()) {
// notifyMonitor(IterationMonitoring.Event.SYNC_STARTING, currentIteration);
if (log.isInfoEnabled()) {
log.info(formatLogString("starting iteration [" + currentIteration + "]"));
}
// this call listens for events until the end-of-superstep is reached
readHeadEventChannel(dummy);
if (log.isInfoEnabled()) {
log.info(formatLogString("finishing iteration [" + currentIteration + "]"));
}
if (checkForConvergence()) {
if (log.isInfoEnabled()) {
log.info(
formatLogString(
"signaling that all workers are to terminate in iteration ["
+ currentIteration
+ "]"));
}
requestTermination();
sendToAllWorkers(new TerminationEvent());
// notifyMonitor(IterationMonitoring.Event.SYNC_FINISHED, currentIteration);
} else {
if (log.isInfoEnabled()) {
log.info(
formatLogString(
"signaling that all workers are done in iteration [" + currentIteration + "]"));
}
AllWorkersDoneEvent allWorkersDoneEvent = new AllWorkersDoneEvent(aggregators);
sendToAllWorkers(allWorkersDoneEvent);
// reset all aggregators
for (Aggregator<?> agg : aggregators.values()) {
agg.reset();
}
// notifyMonitor(IterationMonitoring.Event.SYNC_FINISHED, currentIteration);
currentIteration++;
}
}
}