Hi For now we use very old netty version.
Netty 4.0.27.Final released on 02-Apr-15 <!-- Don't upgrade for now. Netty versions >= 4.0.28.Final contain an improvement by Netty, which slices a Netty buffer instead of doing a memory copy [1] in the LengthFieldBasedFrameDecoder. In some situations, this interacts badly with our Netty pipeline leading to OutOfMemory errors. [1] https://github.com/netty/netty/issues/3704 --> If we so worry about slice in LengthFieldBasedFrameDecoder we can add custom LengthFieldBasedCopyFrameDecoder which extend original LengthFieldBasedFrameDecoder and override extractFrame for keep current behavior. With this small changes we can update for last 4.0.x. For now LengthFieldBasedFrameDecoder also used in KvStateClient and KvStateServer. Can we keep use original LengthFieldBasedFrameDecoder or must also change on LengthFieldBasedCopyFrameDecoder? If we want we can migrate on 4.1. I already did tests and all work correctly, small changes in NettyBufferPool.java and ChunkedByteBuf.java is required (implement new method which added to interface). Thanks Alexey Diomin