Remote Procedure Call (RPC)

HealthCheckThread is replaced by StartHealthCheck function in socket.cpp, but some of the docs/comments are not modified correspondingly. There are 3 files that HealthCheckThread is involved in:

• test/brpc_socket_unittest.cpp(3 occurrences)
• docs/cn/load_balancing.md(1 occurrence)
• src/brpc/socket.h(1 occurrence)

All sentences with 'HealthCheckThread' should be rewritten to sync with the

The MinSendBackupAfterMs is now set to 1 ms. Unfortunately this causes backup requests to be send when there is low load. It would be useful if we could set the minimum a little bit higher for certain endpoints.

JSON is the dominant exchange format for REST API.
However, Armeria's WebClient does not provide any JSON-specific APIs.
I believe it should be useful additions if we provide:

WebClient client = WebClient.of();
// Send a serialized JSON object with "applicaiton/json"
HttpResponse response = client.postJson("/items", new MyItem()); 
HttpResponse response = client.putJson("/items"

We hope mores developers join CloudWeGo. This is a task issue which need your help.

Issue Description
Write a business demo code use Kitex, which can guide users how to use Kitex.
Please submit your code to https://github.com/cloudwego/kitex-examples/bizdemo/{yourdemo}.

Picked

• TODO by @longlihale