How is the distribution of incoming requests among services carried out when using gRPC?

In gRPC, the distribution of incoming requests among services is usually implemented at the client level or with external load balancers. gRPC itself does not provide a built-in load balancing mechanism but supports several strategies:

• Client-side load balancing: the client receives a list of available servers (for example, via service discovery) and distributes requests among them according to an algorithm (round-robin, random selection, etc.).
• Server-side load balancer: external load balancers (such as Envoy, Nginx, or cloud LB) can be used to accept requests and distribute them among service instances.

Example of client-side load balancing using resolver and balancer in Go:

conn, err := grpc.Dial("dns:///myservice.example.com", grpc.WithDefaultServiceConfig(`{"loadBalancingPolicy":"round_robin"}`))

Here, the client uses DNS to obtain a list of servers and applies the round_robin strategy to distribute requests.