General performance improvements

[franklee26]

Of course as part of MVP, we want to focus on core functionality eg. handshake, tls support, streaming and flow control. However, if the mvp implementation is under-performant then we need to make some investments to ensure this doesn't become a larger issue in the future.

The primary concern as of now is how the read workers operate. We will need to analyse some benchmarks and generate some flamegraphs to determine where our bottlenecks lie.