grpclb ClientStats endpoint correlation

[Johan Haals]

 Hi,

It would be fantastic if someone could provide some more context on ClientStats(https://github.com/grpc/grpc/blob/master/src/proto/grpc/lb/v1/load_balancer.proto#L66) and how it's supposed to be used. It looks like stats aren't broken down by endpoint which I would expect to make load balancing decisions. Are there docs or implementations available on lookaside load balancing with Load Reporting from the servers? I can't find that much except for https://github.com/grpc/grpc/blob/master/doc/load-balancing.md#architecture and what's currently being worked on in grpc core.

Best,

Johan

[Carl Mastrangelo]

The Client Stats are for the endpoint you are requesting address / load balancing info, so there's only one.   I don't believe there are docs, but there is an implementation in C++ IIUC.  Look up "load_reporter" (the server side) and "load_balancer" (the client side) in the grpc/grpc repo: https://github.com/grpc/grpc/search?q=load_reporter&unscoped_q=load_reporter

[to...@spotify.com]

Is the plan to only rely on retries/hedging for avoiding slow backends? 

If there is issues between a client and backend that is only visible to the client we, currently, can't act on that based on the ClientStats nor the server LoadBalancingFeedback?