带2个CPU的服务器

Question

I'm building a GRPC server in GO and I want increase its performance. I've increased my machine and put 2CPUS in order to make it better but I noticed that my server doesn't use all cpu cores and I couldn't find a way to fix it (I've run some tests to make the server worker harder). It seems like my server uses 1 cpu a lot and the other not. My load average stay above 1 what means that my server is full of requests but when I see the performance in netdata there's only one CPU working.

This is my grpc code:

package main
import (
    "fmt"
    "runtime"
    "log"
    "net"
    "google.golang.org/grpc"
    "golang.org/x/net/context"
    "google.golang.org/grpc/reflection"
    pb "teste/prototeste"

)
func (s *server) Test(ctx context.Context, n *pb.TestRequest)      (*pb.TestReply, error){
    return &pb.TestReply{Message: n.Name}, nil
}

type server struct{}

const (
    port = ":50051"
)

func main(){

    numOfCores := runtime.NumCPU()
    fmt.Println(numOfCores)
    runtime.GOMAXPROCS(numOfCores)
    lis, err := net.Listen("tcp", port)
    if err != nil {
        log.Fatalf("failed to listen: %v", err)
    }
    s := grpc.NewServer()
    pb.RegisterGreeterServer(s, &server{})
    // Register reflection service on gRPC server.
    reflection.Register(s)

    s.Serve(lis)

}

Notice that in Serve function there's a goroutine that allow the server accept multiple requests in parallel.

API reference grpc in go

This is my cpu usage

Any tips to how to solve this and make my server use 2 cpus?

Answer 1

In gRPC, each server handler runs in its own goroutine. From there it is up to the Go scheduler to determine what CPUs to schedule them on. Depending on what your server handlers are doing, system load, etc, it's possible they could all end up scheduled on the same CPU.