Depois de iniciar o Kafka Connect (connect-standalone), minha tarefa falha imediatamente após iniciar com:

java.lang.OutOfMemoryError: Java heap space
    at java.nio.HeapByteBuffer.<init>(HeapByteBuffer.java:57)
    at java.nio.ByteBuffer.allocate(ByteBuffer.java:335)
    at org.apache.kafka.common.network.NetworkReceive.readFromReadableChannel(NetworkReceive.java:93)
    at org.apache.kafka.common.network.NetworkReceive.readFrom(NetworkReceive.java:71)
    at org.apache.kafka.common.network.KafkaChannel.receive(KafkaChannel.java:154)
    at org.apache.kafka.common.network.KafkaChannel.read(KafkaChannel.java:135)
    at org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:343)
    at org.apache.kafka.common.network.Selector.poll(Selector.java:291)
    at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:260)
    at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:232)
    at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:180)
    at org.apache.kafka.clients.consumer.internals.AbstractCoordinator.ensureCoordinatorReady(AbstractCoordinator.java:193)
    at org.apache.kafka.clients.consumer.internals.ConsumerCoordinator.poll(ConsumerCoordinator.java:248)
    at org.apache.kafka.clients.consumer.KafkaConsumer.pollOnce(KafkaConsumer.java:1013)
    at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:979)
    at org.apache.kafka.connect.runtime.WorkerSinkTask.pollConsumer(WorkerSinkTask.java:316)
    at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:222)
    at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:170)
    at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:142)
    at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:140)
    at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:175)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Há uma menção de espaço de heap em alguma documentação do Kafka, solicitando que você tente com "o padrão" e modifique-o apenas se houver problemas, mas não há instruções para modificar o espaço de heap.