Merge branch 'main' into 24398-quiescence-follow-up

Author: AlexKehayov

platform-sdk/consensus-hashgraph-impl/src/main/java/org/hiero/consensus/hashgraph/impl/EventImpl.java

@@ -11,6 +11,7 @@
 import org.hiero.consensus.hashgraph.impl.consensus.CandidateWitness;
 import org.hiero.consensus.hashgraph.impl.consensus.DeGen;
 import org.hiero.consensus.hashgraph.impl.consensus.LocalConsensusGeneration;
+import org.hiero.consensus.hashgraph.impl.metrics.Sequencer;
 import org.hiero.consensus.model.event.EventDescriptorWrapper;
 import org.hiero.consensus.model.event.LinkedEvent;
 import org.hiero.consensus.model.event.PlatformEvent;
@@ -77,6 +78,9 @@ public class EventImpl extends LinkedEvent<EventImpl> implements Clearable {
     /** The deterministic generation, see {@link DeGen} */
     private int deGen = 0;
 
+    /** A unique sequence number determining the order in which this event was processed */
+    private long sequence = Sequencer.NO_SEQUENCE;
+
     /**
      * Constructor
      *
@@ -519,6 +523,24 @@ public void setDeGen(final int deGen) {
         this.deGen = deGen;
     }
 
+    /**
+     * Get the sequence number of this event, which determines the order in which this event was processed.
+     *
+     * @return the sequence number of this event
+     */
+    public long getSequence() {
+        return sequence;
+    }
+
+    /**
+     * Set the sequence number of this event, which determines the order in which this event was processed.
+     *
+     * @param sequence the sequence number to set
+     */
+    public void setSequence(final long sequence) {
+        this.sequence = sequence;
+    }
+
     //
     // Overrides
     //

platform-sdk/consensus-hashgraph-impl/src/main/java/org/hiero/consensus/hashgraph/impl/consensus/ConsensusImpl.java

@@ -713,7 +713,7 @@ private List<EventImpl> getStronglySeenInPreviousRound(final EventImpl event) {
                         .map(EventImpl::getBaseEvent)
                         .toList();
         // all rounds before this round are now decided, and appropriate events marked consensus
-        consensusMetrics.consensusReachedOnRound();
+        consensusMetrics.consensusReachedOnRound(decidedRoundNumber);
 
         // lastConsensusTime is updated above with the last transaction in the last event that reached consensus
         // if no events reach consensus, then we need to calculate the lastConsensusTime differently

platform-sdk/consensus-hashgraph-impl/src/main/java/org/hiero/consensus/hashgraph/impl/metrics/ConsensusMetrics.java

@@ -32,8 +32,9 @@ public interface ConsensusMetrics {
 
     /**
      * Update a statistics accumulator a round has reached consensus.
+     * @param round the round number that reached consensus
      */
-    void consensusReachedOnRound();
+    void consensusReachedOnRound(final long round);
 
     /**
      * Update a statistics accumulator when an event reaches consensus
@@ -69,20 +70,6 @@ public interface ConsensusMetrics {
      */
     void roundIncrementedByStronglySeen();
 
-    /**
-     * Returns the average difference in creation time and consensus time for self events.
-     *
-     * @return the weighted mean
-     */
-    double getAvgSelfCreatedTimestamp();
-
-    /**
-     * Returns the average difference in creation time and consensus time for other events.
-     *
-     * @return weighted mean
-     */
-    double getAvgOtherReceivedTimestamp();
-
     /**
      * Report the weight of the judges when a round comes to consensus.
      *

platform-sdk/consensus-hashgraph-impl/src/main/java/org/hiero/consensus/hashgraph/impl/metrics/ConsensusMetricsImpl.java

@@ -99,6 +99,10 @@ public class ConsensusMetricsImpl implements ConsensusMetrics {
 
     private final Counter roundIncrementedByStronglySeen;
 
+    private final AverageAndMax numVotingRounds;
+    private final AverageAndMax numEventsAddedUntilConsensus;
+    private final AverageAndMax graphDepthUntilConsensus;
+
     private final NodeId selfId;
 
     /**
@@ -112,6 +116,8 @@ public class ConsensusMetricsImpl implements ConsensusMetrics {
      */
     private static volatile long lastRoundNumber = -1;
 
+    private final Sequencer sequencer = new Sequencer();
+
     /**
      * Constructor of {@code ConsensusMetricsImpl}
      *
@@ -146,6 +152,25 @@ public ConsensusMetricsImpl(final NodeId selfId, final Metrics metrics) {
                         + "created",
                 FORMAT_4_2);
         roundIncrementedByStronglySeen = metrics.getOrCreate(ROUND_INCREMENT_STRONGLY_SEEN_CONFIG);
+
+        numVotingRounds = new AverageAndMax(
+                metrics,
+                INTERNAL_CATEGORY,
+                "numVotingRounds",
+                "number of voting rounds until consensus is reached",
+                FORMAT_10_3);
+        numEventsAddedUntilConsensus = new AverageAndMax(
+                metrics,
+                INTERNAL_CATEGORY,
+                "numEventsAddedUntilConsensus",
+                "after adding event E, how many events are added before E reaches consensus",
+                FORMAT_10_3);
+        graphDepthUntilConsensus = new AverageAndMax(
+                metrics,
+                INTERNAL_CATEGORY,
+                "graphDepthUntilConsensus",
+                "depth of the graph needed to reach consensus (in generations)",
+                FORMAT_10_3);
     }
 
     /**
@@ -154,6 +179,7 @@ public ConsensusMetricsImpl(final NodeId selfId, final Metrics metrics) {
     @Override
     public void addedEvent(final EventImpl event) {
         // this method is only ever called by 1 thread, so no need for locks
+        sequencer.assignSequenceNumber(event);
         if (!Objects.equals(selfId, event.getCreatorId())
                 && event.getRoundCreated() > lastRoundNumber) { // if first event in a round
             final Instant now = Instant.now();
@@ -192,15 +218,29 @@ public void lastFamousInRound(final EventImpl event) {
      * {@inheritDoc}
      */
     @Override
-    public void consensusReachedOnRound() {
+    public void consensusReachedOnRound(final long round) {
         roundsPerSecond.cycle();
+        final EventImpl lastEventAdded = sequencer.getLastEventAdded();
+        if (lastEventAdded != null) {
+            // we have reached consensus for a round, so the last event that we added decided fame
+            // the difference between the round number of the event that decided fame and the consensus round gives us
+            // the number of voting rounds that were needed to reach consensus for this round
+            numVotingRounds.update(lastEventAdded.getRoundCreated() - round);
+        }
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void consensusReached(final EventImpl event) {
+        final EventImpl lastEventAdded = sequencer.getLastEventAdded();
+        if (lastEventAdded != null) {
+            // this should never be null
+            // but if there is a bug, its better to not have metrics than to throw an NPE
+            numEventsAddedUntilConsensus.update(lastEventAdded.getSequence() - event.getSequence());
+            graphDepthUntilConsensus.update(lastEventAdded.getDeGen() - event.getDeGen());
+        }
         // Keep a running average of how many seconds from when I first know of an event
         // until it achieves consensus. Actually, keep two such averages: one for events I
         // create, and one for events I receive.
@@ -237,23 +277,7 @@ public void dotProductTime(final long nanoTime) {
      * {@inheritDoc}
      */
     @Override
-    public double getAvgSelfCreatedTimestamp() {
-        return avgSelfCreatedTimestamp.get();
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public double getAvgOtherReceivedTimestamp() {
-        return avgOtherReceivedTimestamp.get();
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public void judgeWeights(long weight) {
+    public void judgeWeights(final long weight) {
         avgJudgesWeight.update(weight);
     }
 

platform-sdk/consensus-hashgraph-impl/src/main/java/org/hiero/consensus/hashgraph/impl/metrics/NoOpConsensusMetrics.java

@@ -20,7 +20,7 @@ public void lastFamousInRound(final EventImpl event) {
     }
 
     @Override
-    public void consensusReachedOnRound() {
+    public void consensusReachedOnRound(final long round) {
         // no-op
     }
 
@@ -34,16 +34,6 @@ public void dotProductTime(final long nanoTime) {
         // no-op
     }
 
-    @Override
-    public double getAvgSelfCreatedTimestamp() {
-        return 0;
-    }
-
-    @Override
-    public double getAvgOtherReceivedTimestamp() {
-        return 0;
-    }
-
     @Override
     public void judgeWeights(long weight) {
         // no-op

platform-sdk/consensus-hashgraph-impl/src/main/java/org/hiero/consensus/hashgraph/impl/metrics/Sequencer.java

@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: Apache-2.0
+package org.hiero.consensus.hashgraph.impl.metrics;
+
+import edu.umd.cs.findbugs.annotations.NonNull;
+import edu.umd.cs.findbugs.annotations.Nullable;
+import org.hiero.consensus.hashgraph.impl.EventImpl;
+
+/**
+ * Assigns an auto-incrementing sequence number to events as they are added to the system. This is used for metrics purposes.
+ */
+public class Sequencer {
+    /** The first sequence number assigned to an event. */
+    public static final long FIRST_SEQUENCE = 1L;
+    /** A sequence number that indicates that the event has not been assigned a sequence number. */
+    public static final long NO_SEQUENCE = -1L;
+    /** The next sequence number to assign to an event. */
+    private long nextIndex = FIRST_SEQUENCE;
+    /** The last event that was added to the system. */
+    private EventImpl lastEventAdded = null;
+
+    /**
+     * Assigns a sequence number to the given event and updates the last event added. The sequence number is assigned
+     * in the order that events are added to the system.
+     *
+     * @param event the event to assign a sequence number to
+     */
+    public void assignSequenceNumber(@NonNull final EventImpl event) {
+        event.setSequence(nextIndex);
+        nextIndex++;
+        lastEventAdded = event;
+    }
+
+    /**
+     * Gets the last event that was added to the system
+     *
+     * @return the last event that was added to the system, or null if no events have been added
+     */
+    public @Nullable EventImpl getLastEventAdded() {
+        return lastEventAdded;
+    }
+}