Bulk Operation

SPARK-2468 Disable thread local cache in PooledByteBufAllocator

SPARK-2468 SO_RCVBUF and SO_SNDBUF should be bootstrap childOption, not option

SPARK-2468 Refactor Netty module to use BlockTransferService

SPARK-2468 Make sure client doesn't block when server/connection has error(s)

SPARK-2468 Release all ManagedBuffers upon task completion/failure

SPARK-2468 Implement unit/integration tests for connection failures

SPARK-2468 Client should be able to put blocks in addition to fetch blocks

SPARK-2468 Maintains a connection pool and reuse clients in BlockClientFactory

SPARK-2468 Recycle ByteBufs by using PooledByteBufAllocator

SPARK-2468 Use a single FileClient and Netty client thread pool

SPARK-2468 Leverage Hadoop native io's fadvise and read-ahead in Netty transferTo

SPARK-2468 Support transferring large blocks in Netty network module

SPARK-2468 Create config options for Netty sendBufferSize and receiveBufferSize

SPARK-2468 Report error messages back from server to client

SPARK-2468 Add config option to support NIO vs OIO in Netty network module

SPARK-2468 Support fetching multiple blocks in a single request in Netty network module

SPARK-2468 Support fetching in-memory blocks for Netty network module

SPARK-2468 Support SASL authentication in Netty network module

SPARK-2468 Migrate Netty network module from Java to Scala