Add failure per seconds as a series in the chart

locust/static/locust.js

@@ -137,7 +137,7 @@ $(".stats_label").click(function(event) {
 });
 
 // init charts
-var rpsChart = new LocustLineChart($(".charts-container"), "Total Requests per Second", ["RPS"], "reqs/s");
+var rpsChart = new LocustLineChart($(".charts-container"), "Total Requests per Second", ["RPS", "FPS"], "reqs/s");
 var responseTimeChart = new LocustLineChart($(".charts-container"), "Response Times (ms)", ["Median Response Time", "95% percentile"], "ms");
 var usersChart = new LocustLineChart($(".charts-container"), "Number of Users", ["Users"], "users");
 
@@ -159,7 +159,7 @@ function updateStats() {
             // get total stats row
             var total = report.stats[report.stats.length-1];
             // update charts
-            rpsChart.addValue([total.current_rps]);
+            rpsChart.addValue([total.current_rps, total.current_fps]);
             responseTimeChart.addValue([report.current_response_time_percentile_50, report.current_response_time_percentile_95]);
             usersChart.addValue([report.user_count]);
         }

locust/stats.py

@@ -178,6 +178,9 @@ class StatsEntry(object):
 
     num_reqs_per_sec = None
     """ A {second => request_count} dict that holds the number of requests made per second """
+
+    num_fail_per_sec = None
+    """ A (second => failure_count) dict that hold the number of failures per second """    
 
     response_times = None
     """
@@ -231,6 +234,7 @@ def reset(self):
         self.max_response_time = 0
         self.last_request_timestamp = None
         self.num_reqs_per_sec = {}
+        self.num_fail_per_sec = {}
         self.total_content_length = 0
         if self.use_response_times_cache:
             self.response_times_cache = OrderedDict()
@@ -286,6 +290,8 @@ def _log_response_time(self, response_time):
 
     def log_error(self, error):
         self.num_failures += 1
+        t = int(time.time())
+        self.num_fail_per_sec[t] = self.num_fail_per_sec.setdefault(t, 0) + 1
 
     @property
     def fail_ratio(self):
@@ -330,6 +336,15 @@ def current_rps(self):
         reqs = [self.num_reqs_per_sec.get(t, 0) for t in range(slice_start_time, self.stats.last_request_timestamp-2)]
         return avg(reqs)
 
+    @property
+    def current_fps(self):
+        if self.stats.last_request_timestamp is None:
+            return 0
+        slice_start_time = max(self.stats.last_request_timestamp - 12, int(self.stats.start_time or 0))
+
+        reqs = [self.num_fail_per_sec.get(t, 0) for t in range(slice_start_time, self.stats.last_request_timestamp-2)]
+        return avg(reqs)
+
     @property
     def total_rps(self):
         if not self.stats.last_request_timestamp or not self.stats.start_time:
@@ -370,7 +385,9 @@ def extend(self, other):
         for key in other.response_times:
             self.response_times[key] = self.response_times.get(key, 0) + other.response_times[key]
         for key in other.num_reqs_per_sec:
-            self.num_reqs_per_sec[key] = self.num_reqs_per_sec.get(key, 0) +  other.num_reqs_per_sec[key]
+            self.num_reqs_per_sec[key] = self.num_reqs_per_sec.get(key, 0) + other.num_reqs_per_sec[key]
+        for key in other.num_fail_per_sec:
+            self.num_fail_per_sec[key] = self.num_fail_per_sec.get(key, 0) + other.num_fail_per_sec[key]
 
     def serialize(self):
         return {
@@ -387,6 +404,7 @@ def serialize(self):
             "total_content_length": self.total_content_length,
             "response_times": self.response_times,
             "num_reqs_per_sec": self.num_reqs_per_sec,
+            "num_fail_per_sec": self.num_fail_per_sec,
         }
 
     @classmethod
@@ -404,6 +422,7 @@ def unserialize(cls, data):
             "total_content_length",
             "response_times",
             "num_reqs_per_sec",
+            "num_fail_per_sec",
         ]:
             setattr(obj, key, data[key])
         return obj
@@ -419,15 +438,16 @@ def get_stripped_report(self):
     def __str__(self):
         fail_percent = self.fail_ratio * 100
 
-        return (" %-" + str(STATS_NAME_WIDTH) + "s %7d %12s %7d %7d %7d  | %7d %7.2f") % (
+        return (" %-" + str(STATS_NAME_WIDTH) + "s %7d %12s %7d %7d %7d  | %7d %7.2f %7.2f") % (
             (self.method and self.method + " " or "") + self.name,
             self.num_requests,
             "%d(%.2f%%)" % (self.num_failures, fail_percent),
             self.avg_response_time,
             self.min_response_time or 0,
             self.max_response_time,
             self.median_response_time or 0,
-            self.current_rps or 0
+            self.current_rps or 0,
+            self.current_fps or 0
         )
 
     def get_response_time_percentile(self, percent):
@@ -639,11 +659,13 @@ def print_stats(stats):
     console_logger.info((" %-" + str(STATS_NAME_WIDTH) + "s %7s %12s %7s %7s %7s  | %7s %7s") % ('Name', '# reqs', '# fails', 'Avg', 'Min', 'Max', 'Median', 'req/s'))
     console_logger.info("-" * (80 + STATS_NAME_WIDTH))
     total_rps = 0
+    total_fps = 0
     total_reqs = 0
     total_failures = 0
     for key in sorted(six.iterkeys(stats)):
         r = stats[key]
         total_rps += r.current_rps
+        total_fps += r.current_fps
         total_reqs += r.num_requests
         total_failures += r.num_failures
         console_logger.info(r)

locust/test/test_stats.py

@@ -63,6 +63,16 @@ def test_current_rps(self):
         self.stats.total.last_request_timestamp = int(time.time()) + 25
         self.assertEqual(self.s.current_rps, 0)
 
+    def test_current_fps(self):
+        self.stats.total.last_request_timestamp = int(time.time()) + 4
+        self.assertEqual(self.s.current_fps, 1.5)
+
+        self.stats.total.last_request_timestamp = int(time.time()) + 12
+        self.assertEqual(self.s.current_fps, 0.3)
+
+        self.stats.total.last_request_timestamp = int(time.time()) + 25
+        self.assertEqual(self.s.current_fps, 0)
+
     def test_num_reqs_fails(self):
         self.assertEqual(self.s.num_requests, 9)
         self.assertEqual(self.s.num_failures, 3)

locust/web.py

@@ -134,6 +134,7 @@ def request_stats():
             "min_response_time": 0 if s.min_response_time is None else proper_round(s.min_response_time),
             "max_response_time": proper_round(s.max_response_time),
             "current_rps": s.current_rps,
+            "current_fps": s.current_fps,
             "median_response_time": s.median_response_time,
             "ninetieth_response_time": s.get_response_time_percentile(0.9),
             "avg_content_length": s.avg_content_length,