[WIP] Peer rate-limiting

[pm47]

No description provided.

[n1bor]

Any plans to merge this? Just be really good to get the metrics bit merged as was wanting to add a lot more.
So understand what is actually going on in the node and what it is spending time doing.

[pm47]

This branch is currently running on our production node: the goal is to gather information on the current state of the network and find out the best way to implement peer rate limiting, but the actual work hasn't started yet.

[n1bor]

Was just wanting to have the codehale metrics commit merged - rather than the rate limiting bit.
Then I can add a number of PR's for:
Timing round some of the db calls.
Rate of events on the EventBus
Cached gauges on number of nodes/channels etc..
Return some of the cached guages in getinfo API call.

Also did you see you can use annotations?
https://metrics.dropwizard.io/4.0.0/apidocs/com/codahale/metrics/annotation/Gauge.html