我最近启用了ssl，并尝试在分布式模式下启动kafka connect。运行时

connect-distributed connect-distributed.properties

我得到以下错误：

[2018-10-09 16:50:57,190] INFO Stopping task (io.confluent.connect.jdbc.sink.JdbcSinkTask:106)
[2018-10-09 16:50:55,471] ERROR WorkerSinkTask{id=sink-mariadb-test} Task threw an uncaught and unrecoverable exception (org.apache.kafka.connect.runtime.WorkerTask:177)
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.memory.MemoryPool$1.tryAllocate(MemoryPool.java:30)
        at org.apache.kafka.common.network.NetworkReceive.readFrom(NetworkReceive.java:112)
        at org.apache.kafka.common.network.KafkaChannel.receive(KafkaChannel.java:344)
        at org.apache.kafka.common.network.KafkaChannel.read(KafkaChannel.java:305)
        at org.apache.kafka.common.network.Selector.attemptRead(Selector.java:560)
        at org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:496)
        at org.apache.kafka.common.network.Selector.poll(Selector.java:425)
        at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:510)
        at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:271)
        at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:242)
        at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:218)
        at org.apache.kafka.clients.consumer.internals.AbstractCoordinator.ensureCoordinatorReady(AbstractCoordinator.java:230)
        at org.apache.kafka.clients.consumer.internals.ConsumerCoordinator.poll(ConsumerCoordinator.java:314)
        at org.apache.kafka.clients.consumer.KafkaConsumer.updateAssignmentMetadataIfNeeded(KafkaConsumer.java:1218)
        at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1181)
        at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1115)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.pollConsumer(WorkerSinkTask.java:444)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:317)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:225)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:193)
        at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:175)
        at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:219)
        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:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)

以及

java.lang.OutOfMemoryError: Direct buffer memory
        at java.nio.Bits.reserveMemory(Bits.java:694)
        at java.nio.DirectByteBuffer.<init>(DirectByteBuffer.java:123)
        at java.nio.ByteBuffer.allocateDirect(ByteBuffer.java:311)
        at sun.nio.ch.Util.getTemporaryDirectBuffer(Util.java:241)
        at sun.nio.ch.IOUtil.read(IOUtil.java:195)
        at sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:380)
        at org.apache.kafka.common.network.PlaintextTransportLayer.read(PlaintextTransportLayer.java:104)
        at org.apache.kafka.common.network.NetworkReceive.readFrom(NetworkReceive.java:117)
        at org.apache.kafka.common.network.KafkaChannel.receive(KafkaChannel.java:344)
        at org.apache.kafka.common.network.KafkaChannel.read(KafkaChannel.java:305)
        at org.apache.kafka.common.network.Selector.attemptRead(Selector.java:560)
        at org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:496)
        at org.apache.kafka.common.network.Selector.poll(Selector.java:425)
        at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:510)
        at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:271)
        at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:242)
        at org.apache.kafka.clients.consumer.internals.ConsumerNetworkClient.poll(ConsumerNetworkClient.java:218)
        at org.apache.kafka.clients.consumer.internals.AbstractCoordinator.ensureCoordinatorReady(AbstractCoordinator.java:230)
        at org.apache.kafka.clients.consumer.internals.ConsumerCoordinator.poll(ConsumerCoordinator.java:314)
        at org.apache.kafka.clients.consumer.KafkaConsumer.updateAssignmentMetadataIfNeeded(KafkaConsumer.java:1218)
        at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1181)
        at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1115)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.pollConsumer(WorkerSinkTask.java:444)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.poll(WorkerSinkTask.java:317)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.iteration(WorkerSinkTask.java:225)
        at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:193)
        at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:175)
        at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:219)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
        at java.lang.Thread.run(Thread.java:748)

我还尝试通过运行

KAFKA_HEAP_OPTS="-Xms4g -Xmx6g" connect-distributed connect-distributed.properties

但还是不行。
我的问题是：
ssl身份验证会影响内存使用吗？
我如何解决这个问题？
编辑：
我已经尝试禁用ssl，一切正常。