private static JobTaskVertex createIterationHead(
JobGraph jobGraph, int numSubTasks, TypeSerializerFactory<?> serializer) {
JobTaskVertex head =
JobGraphUtils.createTask(
IterationHeadPactTask.class, "Iteration Head", jobGraph, numSubTasks, numSubTasks);
TaskConfig headConfig = new TaskConfig(head.getConfiguration());
headConfig.setIterationId(ITERATION_ID);
// initial input / partial solution
headConfig.addInputToGroup(0);
headConfig.setIterationHeadPartialSolutionOrWorksetInputIndex(0);
headConfig.setInputSerializer(serializer, 0);
// back channel / iterations
headConfig.setBackChannelMemory(MEMORY_PER_CONSUMER * JobGraphUtils.MEGABYTE);
// output into iteration. broadcasting the centers
headConfig.setOutputSerializer(serializer);
headConfig.addOutputShipStrategy(ShipStrategyType.BROADCAST);
// final output
TaskConfig headFinalOutConfig = new TaskConfig(new Configuration());
headFinalOutConfig.setOutputSerializer(serializer);
headFinalOutConfig.addOutputShipStrategy(ShipStrategyType.FORWARD);
headConfig.setIterationHeadFinalOutputConfig(headFinalOutConfig);
// the sync
headConfig.setIterationHeadIndexOfSyncOutput(2);
// the driver
headConfig.setDriver(NoOpDriver.class);
headConfig.setDriverStrategy(DriverStrategy.UNARY_NO_OP);
return head;
}
