Negative execution time

[jachinte]

Hi,

I'm testing invokust locally with localstack, and haven't deployed to AWS yet. Everything works well, but I'm getting a negative execution time.

This is a test result; the key total_lambda_execution_time is assigned to this negative value: -582398. It should probably be 15.6032865047 (1663692383.5552292 - 1663692367.9519427), which is consistent with the duration I set for this test (15s).

{
  "summary_stats":{
    "lambda_invocation_count":1,
    "total_lambda_execution_time":-582398,
    "requests_total":1392,
    "request_fail_ratio":0.0,
    "invocation_error_ratio":0.0
  },
  "results":[
    {
      "requests":{
        "GET_/":{
          "request_type":"GET",
          "num_requests":1392,
          "min_response_time":716.8549480848014,
          "median_response_time":2300.0,
          "avg_response_time":3316.3983788552537,
          "max_response_time":14563.939598971047,
          "response_times":{...},
          "response_time_percentiles":{...},
          "total_rps":93.70657030509588,
          "total_rpm":5622.3942183057525
        }
      },
      "failures":{},
      "num_requests":1392,
      "num_requests_fail":0,
      "start_time":1663692367.9519427,
      "end_time":1663692383.5552292,
      "remaining_time":882398,
      "function_name":"locust-function",
      "function_version":"$LATEST",
      "invoked_function_arn":"arn:aws:lambda:us-east-2:000000000000:function:locust-function",
      "memory_limit":"1536",
      "aws_request_id":"2483a0c5-3c47-150a-6b27-c9535e8eeacb",
      "log_group_name":"/aws/lambda/locust-function",
      "log_stream_name":"2022/09/20/[$LATEST]4aff2d740c665b04f425e1c3239ea985"
    }
  ]
}

This is the code I'm using to launch the test:

        load_test: LambdaLoadTest = LambdaLoadTest(
            lambda_function_name=locust_lambda_name,
            threads=threads,
            ramp_time=0,
            time_limit=duration,
            lambda_payload={
                "locust_modules": modules,
                "host": host,
                "num_users": users,
                "spawn_rate": spawn_rate,
                "run_time": f"{duration}s",
            },
        )
        load_test.run()
        result: TestResult = TestResult(
            summary_stats=load_test.get_summary_stats(),
            results=load_test.get_locust_results(),
        )