Netty ByteBuf occupies all memory

Question

I wrote a simple code to test the performance my Server

        while (true) {
            ByteBuf firstMessage = Unpooled.buffer(8);
            firstMessage.writeInt(1);
            firstMessage.writeInt(1);
            firstMessage.writeLong(1L);
            f.channel().writeAndFlush(firstMessage);
        }

After 30 seconds:

• All memory occupied
• Server stop receiving new messages

Sorry my English

Answer 1

Likely you are creating new buffers (on-heap) quicker than you can send them across the network on a single channel, so eventually they consume the whole heap and you'll have OOM problems.

Answer 2

I think you'd better try to call firstMessage.release() after the flushing is done. In the ByteBuf specification, it is shown that the ByteBuffer is implementing ReferenceCounted.

Answer 3

You don't need to keep recreating that buffer. Either release it inside the loop, or create it before the loop starts and just reset it inside the loop.