Question

给定Observable A代表传入请求......

interface IRequest
{
  string Id { get; }
}

IObservable<IRequest> requests;

和Observable B代表回应......

IObservable<string> responses;

我需要测量产生响应所需的时间。我目前的解决方案如下所示。这有效，但我不确定这是否可以简化或实现更精简。我还关注实际响应时间（[GEN]）与观察到的响应时间（[OBS]）之间的偏差，如果generatedResponseTime设置为低于50毫秒，则会变得安静。

class Program
{
    public class Request
    {
        public string Id { get; set; }
    }

    static void Main(string[] args)
    {
        var generatedResponseTime = 100;

        var responseSub = new Subject<string>();

        IObservable<Request> requests = Observable.Interval(TimeSpan.FromMilliseconds(1000))
            .Select(x=> new Request { Id = x.ToString("d") });

        IObservable<string> responses = responseSub.AsObservable();

        var responseTime = requests
            .Where(x => !string.IsNullOrEmpty(x.Id))
            .Select(req => new { Id = req.Id, Start = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds() })
            .SelectMany(req => responses
                .Where(reqId => reqId == req.Id)
                .Select(_ => new { RequestId = req.Id, ResponseTime = (int)(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds() - req.Start) })
                .Take(1))
            .Publish()
            .RefCount();

        requests.ObserveOn(TaskPoolScheduler.Default)
            .Subscribe(req =>
            {
                Console.WriteLine($"[GEN] {req.Id} = {generatedResponseTime} ms");

                Thread.Sleep(generatedResponseTime);
                responseSub.OnNext(req.Id);
            });

        responseTime.Subscribe(x => Console.WriteLine($"[OBS] {x.RequestId} = {x.ResponseTime} ms"));

        Console.ReadLine();
    }
}

Answer 1

这是使用一些内置运算符的替代方案。您的解决方案中也没有多个订阅问题：

Upload

如果您对请求有任何类型的超时标准，那么从性能角度来看，将其放在注释所指示的位置会很有帮助。否则，var responseTime2 = requests .Timestamp() .Join(responses.Timestamp(), request => Observable.Never<Unit>(), //timeout criteria response => Observable.Empty<Unit>(), (request, response) => (request: request, response: response) ) .Where(t => t.request.Value.Id == t.response.Value) .Select(t => t.response.Timestamp.ToUnixTimeMilliseconds() - t.request.Timestamp.ToUnixTimeMilliseconds())组合的表现会随着时间的推移而恶化。

使用可观察量来衡量响应时间

1 个答案: