Analyze changing Stream content to Blocks

[a-saksena]

As a Block Stream designer
I want to have both high throughput and very low latency in the block stream
So that I can deliver the core value proposition of the block stream.

In testing we have seen possible indications that gRPC streaming of individual block items appears to have negative impacts on throughput. A possible resolution is to stream full blocks instead of items.
This task is to examine the options and assess in detail the probable latency impact (e.g. does this delay the start of sending a block until the end of a round in consensus?) and other follow-on effects to ensure we have an efficient low-latency and high-throughput design.