Can someone help me understand the difference between a memory segment and a network buffer? It seems the

Status.Shuffle.Netty.TotalMemorySegments

is tied the

taskmanager.memory.network.fraction

which is described as

Direct memory reserved for data record exchange between tasks (e.g. buffering for the transfer over the network), is a capped fractionated component of the total Flink memory. This memory is used for allocation of network buffers

but the correlation doesn't seem 1 to 1. what is being additionally measured here?