Begin implementation of dynamic throttling framework

perf/throttle.py

@@ -0,0 +1,79 @@
+import psutil
+import asyncio
+import time
+import util
+
+class DynamicThrottle(object):
+
+    def __init__(self, **kwargs):
+        self.target_cpu_usage = kwargs.get("target_cpu_usage", 50)
+        self.sleep_interval = 0.0
+
+        self.sleep_increment = kwargs.get("sleep_increment", 0.01)
+        self.sleep_decrement = kwargs.get("sleep_decrement", 0.01)
+
+        self.sleep_max = kwargs.get("sleep_max", 0.1)
+        self.sleep_min = kwargs.get("sleep_min", 0.01)
+
+        self.psutil_interval = kwargs.get("psutil_interval", 0.1)
+
+        self.log = kwargs.get("log", util.get_logger(self.__class__.__name__))
+
+        self.consecutive_increments = 0
+        self.consecutive_decrements = 0
+
+        self.last_was_increment = False
+
+        if kwargs.get("async"):
+            self.dynamic_throttle = self.dynamic_throttle_async
+        else:
+            self.dynamic_throttle = self.dynamic_throttle
+
+
+    async def dynamic_throttle_async(self):
+        """
+        Dynamically sleeps before a request if CPU usage is above our target.
+        """
+        current_cpu_usage = psutil.cpu_percent(interval=self.psutil_interval)
+
+        if current_cpu_usage > self.target_cpu_usage:
+            self.sleep_interval += self.sleep_increment
+            if self.sleep_interval > self.sleep_max:
+                self.sleep_interval = self.sleep_max
+            self.log.info(
+                f"CPU {current_cpu_usage}% > {self.target_cpu_usage}%, "
+                f"=> sleep {self.sleep_interval:.3f}s"
+            )
+        elif current_cpu_usage < self.target_cpu_usage and self.sleep_interval > self.sleep_min:
+            self.sleep_interval -= self.sleep_decrement
+            self.log.info(
+                f"CPU {current_cpu_usage}% < {self.target_cpu_usage}%, "
+                f"=> sleep {self.sleep_interval:.3f}s"
+            )
+
+        if self.sleep_interval > 0:
+            await asyncio.sleep(self.sleep_interval)
+
+    def dynamic_throttle(self):
+        """
+        Dynamically sleeps before a request if CPU usage is above our target.
+        """
+        current_cpu_usage = psutil.cpu_percent(interval=self.psutil_interval)
+
+        if current_cpu_usage > self.target_cpu_usage:
+            self.sleep_interval += self.sleep_increment
+            if self.sleep_interval > self.sleep_max:
+                self.sleep_interval = self.sleep_max
+            self.log.info(
+                f"CPU {current_cpu_usage}% > {self.target_cpu_usage}%, "
+                f"=> sleep {self.sleep_interval:.3f}s"
+            )
+        elif current_cpu_usage < self.target_cpu_usage and self.sleep_interval > self.sleep_min:
+            self.sleep_interval -= self.sleep_decrement
+            self.log.info(
+                f"CPU {current_cpu_usage}% < {self.target_cpu_usage}%, "
+                f"=> sleep {self.sleep_interval:.3f}s"
+            )
+
+        if self.sleep_interval > 0:
+            time.sleep(self.sleep_interval)