traffic-control: (fixes #2512, #2590) Various small fixes regarding the RED queue disc

RELEASE_NOTES

@@ -33,6 +33,7 @@ Bugs fixed
 - Bug 2485 - Check for queue full should happen before checking RED thresholds
 - Bug 2492 - uan: Make use of RxGain attribute in UanPhyGen class
 - Bug 2511 - HT Greenfield is not working
+- Bug 2512 - Byte mode not configured correctly in red-queue-disc-test-suite.cc
 - Bug 2513 - ParetoRandomVariable needs a "scale", not a "mean" attribute.
 - Bug 2521 - Include ipv6-option.h in wscript
 - Bug 2527 - PrintRoutingTable extended to add an optional Time::Units parameter
@@ -56,6 +57,7 @@ Bugs fixed
 - Bug 2566 - BlockAckManager::GetNRetryNeededPackets missing some packets in the queue
 - Bug 2577 - simulation crashes when A-MPDU and multiple TOS are used with RTS-CTS enabled
 - Bug 2584 - MacLow triggers StartNext even if there is no TXOP
+- Bug 2590 - Minor enhancements in red-queue-disc{.h, .cc}
 - Bug 2591 - 802.11e Block Ack mechanism cannot be enabled on HT/VHT stations
 - Bug 2594 - vht-wifi-network provides very low throughtput at MCS 6, 160 MHz, SGI
 - Bug 2614 - RIP header version should be set to 2

src/traffic-control/model/red-queue-disc.cc

@@ -569,8 +569,11 @@ RedQueueDisc::InitializeParams (void)
 
 // Update m_curMaxP to keep the average queue length within the target range.
 void
-RedQueueDisc::UpdateMaxP (double newAve, Time now)
+RedQueueDisc::UpdateMaxP (double newAve)
 {
+  NS_LOG_FUNCTION (this << newAve);
+
+  Time now = Simulator::Now ();
   double m_part = 0.4 * (m_maxTh - m_minTh);
   // AIMD rule to keep target Q~1/2(m_minTh + m_maxTh)
   if (newAve < m_minTh + m_part && m_curMaxP > m_bottom)
@@ -601,10 +604,10 @@ RedQueueDisc::Estimator (uint32_t nQueued, uint32_t m, double qAvg, double qW)
   double newAve = qAvg * pow(1.0-qW, m);
   newAve += qW * nQueued;
 
-  Time now = Simulator::Now();
+  Time now = Simulator::Now ();
   if (m_isAdaptMaxP && now > m_lastSet + m_interval)
     {
-      UpdateMaxP(newAve, now);
+      UpdateMaxP(newAve);
     }
 
   return newAve;

src/traffic-control/model/red-queue-disc.h

@@ -66,7 +66,6 @@
 #include "ns3/nstime.h"
 #include "ns3/boolean.h"
 #include "ns3/data-rate.h"
-#include "ns3/nstime.h"
 #include "ns3/random-variable-stream.h"
 
 namespace ns3 {
@@ -238,9 +237,8 @@ private:
    /**
     * \brief Update m_curMaxP
     * \param newAve new average queue length
-    * \param now Current Time
     */
-  void UpdateMaxP (double newAve, Time now);
+  void UpdateMaxP (double newAve);
   /**
    * \brief Check if a packet needs to be dropped due to probability mark
    * \param item queue item
@@ -320,8 +318,8 @@ private:
   uint32_t m_count;         //!< Number of packets since last random number generation
   /**
    * 0 for default RED
-   * 1 experimental (see red-queue.cc)
-   * 2 experimental (see red-queue.cc)
+   * 1 experimental (see red-queue-disc.cc)
+   * 2 experimental (see red-queue-disc.cc)
    * 3 use Idle packet size in the ptc
    */
   uint32_t m_cautious;

src/traffic-control/test/red-queue-disc-test-suite.cc

@@ -112,7 +112,8 @@ RedQueueDiscTestCase::RunRedTest (StringValue mode)
   
   if (queue->GetMode () == Queue::QUEUE_MODE_BYTES)
     {
-      pktSize = 1000;
+      // pktSize should be same as MeanPktSize to avoid performance gap between byte and packet mode
+      pktSize = 500;
       modeSize = pktSize;
       queue->SetTh (minTh * modeSize, maxTh * modeSize);
       queue->SetQueueLimit (qSize * modeSize);