Fix order of operations in codel control law

robgjansen · robgjansen · commit e513c3879276 · 2022-10-19T20:06:35.000-04:00
diff --git a/src/main/routing/router_queue_codel.c b/src/main/routing/router_queue_codel.c
@@ -197,12 +197,9 @@ static Packet* _routerqueuecodel_dequeueHelper(QueueManagerCoDel* queueManager,
 }
 
 static CSimulationTime _routerqueuecodel_controlLaw(guint count, CSimulationTime ts) {
-    CSimulationTime newTS = ts + CODEL_PARAM_INTERVAL_SIMTIME;
-
-    double result = ((double)newTS) / sqrt((double)count);
-    double rounded = round(result);
-
-    return (CSimulationTime)rounded;
+    // control_law: t + (INTERVAL / sqrt(count));
+    double result = ((double)CODEL_PARAM_INTERVAL_SIMTIME) / sqrt((double)count);
+    return ts + ((CSimulationTime)result);
 }
 
 static Packet* _routerqueuecodel_dequeue(QueueManagerCoDel* queueManager) {

Original file line number	Diff line number	Diff line change
`@@ -197,12 +197,9 @@ static Packet* _routerqueuecodel_dequeueHelper(QueueManagerCoDel* queueManager,`
`197`	`197`	`}`
`198`	`198`
`199`	`199`	`static CSimulationTime _routerqueuecodel_controlLaw(guint count, CSimulationTime ts) {`
`200`		`- CSimulationTime newTS = ts + CODEL_PARAM_INTERVAL_SIMTIME;`
`201`		`-`
`202`		`- double result = ((double)newTS) / sqrt((double)count);`
`203`		`- double rounded = round(result);`
`204`		`-`
`205`		`- return (CSimulationTime)rounded;`
	`200`	`+ // control_law: t + (INTERVAL / sqrt(count));`
	`201`	`+ double result = ((double)CODEL_PARAM_INTERVAL_SIMTIME) / sqrt((double)count);`
	`202`	`+ return ts + ((CSimulationTime)result);`
`206`	`203`	`}`
`207`	`204`
`208`	`205`	`static Packet* _routerqueuecodel_dequeue(QueueManagerCoDel* queueManager) {`