ghz VS grpcurl

I once built a quick and dirty load testing tool for a public facing service we built. The tool was pretty simple - something like https://github.com/bojand/ghz but with traffic and data patterns closer to what we expected to see in the real world. We used argo-workflows to generate scale.

One thing which we noticed was that there was a considerable difference in performance characteristics based on how we parallelized the load testing tool (multiple threads, multiple processes, multiple kubernetes pods, pods forced to be distributed across nodes).

I think that when you run non-distrubuted load tests you benefit from bunch of cool things which happen with http2 and Linux (multiplexing, resource sharing etc) which might make applications seem much faster than they would be in the real world.

I'm not sure. Maybe you can write to the discussion section of the repo https://github.com/bojand/ghz/discussions

In part 1 we looked at ghz for load testing gRPC services, and now I want to cover k6, which claims to be a modern load testing tool built for developer happiness. After only a brief experience with it I can see why is that and why Grafana moved to acquire k6 earlier this year.

It should be unbound, in this particular benchmark we set ghz concurrency to 50 and connections to 5 and we don't set the rps flag of ghz (e.g. --rps=2000, from this tool)

a second container running ghz makes unary requests to the server

grpcurl

The API server will be built and start running on port 50051. You can test the functionality using a gRPC client of your choice like grpcurl or Postman.

> What is the ubiquitous utility for interacting with gRPC? We have curl for REST. What is openAPI of gRPC?

grpcurl[1] combined with gRPC server reflection[2]. The schema is compiled into the server as an encoded proto which is exposed via server reflection, which grpcurl reads to send correctly encoded requests.

[1] https://github.com/fullstorydev/grpcurl

The whole idea behind the post is that accessing the gRPC service with regular tools is impossible. To test, we need a dedicated tool nonetheless. I found grpcurl. Let's install it and use it to list available services:

gRpcurl is a cool little tool to look at btw. Had to use it at my job before. Can call a gRPC via a curl like command. Regular curl doesn't support HTTP2. Had to use TLS with some tokens even. But you can reference a local .proto(gRPC protobuf file for the call) and make things easier for yourself if you hate reading instructions on command line args like I do.

A simple GRPC client built using grpcurl.

Try testing with grpcurl, using the -H or -rpc-header flags to set the appropriate header.