fix(perf): normalize entity hotspot lifetimes

src/main/java/com/moepus/serverwarashi/client/state/ClientPerfWorldState.java

@@ -51,8 +51,15 @@ public final class ClientPerfWorldState {
                                      long tickCount,
                                      long nanosPerSample) {
         var cost = new PerfWorldHotspotIndex.Cost(entry.samples(), entry.maxSamplesQ8());
-        PerfReportData.Metric metric = cost.metric(tickCount, nanosPerSample);
-        return new Hotspot(entry.key(), entry.detailKind(), entry.registryId(), metric);
+        long measurementTicks = measurementTicks(tickCount, entry.measurementStartTick());
+        PerfReportData.Metric metric = cost.metric(measurementTicks, nanosPerSample);
+        return new Hotspot(entry.key(), entry.detailKind(), entry.registryId(),
+                measurementTicks, metric);
+    }
+
+    static long measurementTicks(long tickCount, long measurementStartTick) {
+        return tickCount <= 0L ? 0L
+                : Math.max(1L, tickCount - measurementStartTick + 1L);
     }
 
     public static Snapshot snapshot() {
@@ -67,6 +74,7 @@ public final class ClientPerfWorldState {
     public record Hotspot(PerfWorldHotspotIndex.Key key,
                           TickDetailKind detailKind,
                           int registryId,
+                          long measurementTicks,
                           PerfReportData.Metric metric) {
     }
 

src/main/java/com/moepus/serverwarashi/client/world/WorldEntityFlameClusters.java

@@ -44,7 +44,8 @@ final class WorldEntityFlameClusters {
                 mspt, Math.max(mspt, maximum), samples);
         var anchor = new Anchor(centerX(input.bounds()), input.bounds().maxY,
                 centerZ(input.bounds()));
-        var visual = new Visual(ObjectPerformanceScale.effectiveSamples(metric, tickCount),
+        var visual = new Visual(ObjectPerformanceScale.effectiveSamples(
+                metric, measurementTicks(input, tickCount)),
                 updatePhase(0x811C9DC5, input.stableId()) & 0x7FFF, 1);
         return new Marker(anchor, metric, visual);
     }
@@ -54,6 +55,8 @@ final class WorldEntityFlameClusters {
         double totalMspt = 0.0D;
         double totalMax = 0.0D;
         long totalSamples = 0L;
+        double averageSamples = 0.0D;
+        double maximumSamples = 0.0D;
         double totalWeight = 0.0D;
         double x = 0.0D;
         double z = 0.0D;
@@ -66,6 +69,9 @@ final class WorldEntityFlameClusters {
             totalMspt += mspt;
             totalMax += maximum;
             totalSamples = saturatedAdd(totalSamples, Math.max(0L, input.metric().samples()));
+            long inputTicks = measurementTicks(input, tickCount);
+            averageSamples += ObjectPerformanceScale.averageSamples(input.metric(), inputTicks);
+            maximumSamples += ObjectPerformanceScale.estimatedMaxSamples(input.metric(), inputTicks);
             totalWeight += weight;
             x += centerX(input.bounds()) * weight;
             z += centerZ(input.bounds()) * weight;
@@ -75,10 +81,14 @@ final class WorldEntityFlameClusters {
         PerfReportData.Metric metric = new PerfReportData.Metric(
                 totalMspt, Math.max(totalMspt, totalMax), totalSamples);
         return new Marker(new Anchor(x / totalWeight, y, z / totalWeight), metric,
-                new Visual(ObjectPerformanceScale.effectiveSamples(metric, tickCount),
+                new Visual(ObjectPerformanceScale.effectiveSamples(averageSamples, maximumSamples),
                         phase & 0x7FFF, group.size()));
     }
 
+    private static long measurementTicks(Input input, long fallback) {
+        return input.measurementTicks() > 0L ? input.measurementTicks() : fallback;
+    }
+
     private static double positiveFinite(double value) {
         return Double.isFinite(value) && value > 0.0D ? value : 0.0D;
     }
@@ -103,7 +113,11 @@ final class WorldEntityFlameClusters {
         return (int) Math.floor(coordinate / CELL_SIZE);
     }
 
-    record Input(AABB bounds, PerfReportData.Metric metric, int stableId) {
+    record Input(AABB bounds, PerfReportData.Metric metric,
+                 long measurementTicks, int stableId) {
+        Input(AABB bounds, PerfReportData.Metric metric, int stableId) {
+            this(bounds, metric, 0L, stableId);
+        }
     }
 
     record Anchor(double x, double y, double z) {

src/main/java/com/moepus/serverwarashi/client/world/WorldPerfObjectRenderer.java

@@ -78,7 +78,7 @@ final class WorldPerfObjectRenderer {
         }
         for (ClientPerfWorldState.Hotspot hotspot : snapshot.hotspots()) {
             double effective = ObjectPerformanceScale.effectiveSamples(
-                    hotspot.metric(), snapshot.tickCount());
+                    hotspot.metric(), hotspot.measurementTicks());
             if (WorldOverlayMath.shouldRender(effective, currentFilter)) {
                 next.add(new Candidate(hotspot, hotspot.metric(), effective));
                 if (next.size() == WorldPerfObjectBuffers.MAX_MARKER_COUNT) {
@@ -109,7 +109,8 @@ final class WorldPerfObjectRenderer {
             }
             if (candidate.hotspot().key().kind() == PerfWorldHotspotIndex.Kind.ENTITY) {
                 var input = new WorldEntityFlameClusters.Input(
-                        bounds, candidate.metric(), candidate.hotspot().key().entityId());
+                        bounds, candidate.metric(), candidate.hotspot().measurementTicks(),
+                        candidate.hotspot().key().entityId());
                 if (shouldClusterEntity(candidate.hotspot().detailKind())) {
                     itemEntities.add(input);
                 } else {

src/main/java/com/moepus/serverwarashi/common/modules/performance/report/ObjectPerformanceScale.java

@@ -26,7 +26,13 @@ public final class ObjectPerformanceScale {
 
     public static double effectiveSamples(PerfReportData.Metric metric, long tickCount) {
         double average = averageSamples(metric, tickCount);
-        double burst = Math.max(0.0D, estimatedMaxSamples(metric, tickCount) - average);
+        return effectiveSamples(average, estimatedMaxSamples(metric, tickCount));
+    }
+
+    public static double effectiveSamples(double averageSamples, double estimatedMaxSamples) {
+        double average = bounded(averageSamples);
+        double maximum = bounded(estimatedMaxSamples);
+        double burst = Math.max(0.0D, maximum - average);
         return Math.min(MAX_SAMPLE_VALUE, average + Math.log1p(burst) / LOG_TWO);
     }
 
@@ -36,7 +42,11 @@ public final class ObjectPerformanceScale {
         }
         double averageSamples = samples / (double) tickCount;
         double estimatedMaxSamples = maxSamplesQ8 / (double) PerfWorldHotspotIndex.MAX_SAMPLES_SCALE;
-        double excess = Math.max(0.0D, estimatedMaxSamples - averageSamples);
-        return averageSamples + Math.log1p(excess) / Math.log(2.0D);
+        return effectiveSamples(averageSamples, estimatedMaxSamples);
+    }
+
+    private static double bounded(double value) {
+        return Double.isFinite(value) && value > 0.0D
+                ? Math.min(MAX_SAMPLE_VALUE, value) : 0.0D;
     }
 }

src/main/java/com/moepus/serverwarashi/common/modules/performance/report/PerfWorldHotspotIndex.java

@@ -20,6 +20,9 @@ public record PerfWorldHotspotIndex(long streamEpoch,
             throw new IllegalArgumentException("Hotspot index scalars must be non-negative");
         }
         entries = List.copyOf(entries);
+        if (entries.stream().anyMatch(entry -> entry.measurementStartTick() > tickCount)) {
+            throw new IllegalArgumentException("Hotspot measurement starts after the snapshot");
+        }
     }
 
     public static PerfWorldHotspotIndex empty(long streamEpoch, long revision, long tickCount) {
@@ -52,6 +55,7 @@ public record PerfWorldHotspotIndex(long streamEpoch,
                         int z,
                         TickDetailKind detailKind,
                         ResourceLocation detailId,
+                        long measurementStartTick,
                         long samples,
                         int maxSamplesQ8) {
         public Entry {
@@ -59,8 +63,8 @@ public record PerfWorldHotspotIndex(long streamEpoch,
             Objects.requireNonNull(dimension, "dimension");
             Objects.requireNonNull(detailKind, "detailKind");
             Objects.requireNonNull(detailId, "detailId");
-            if (samples < 0L || maxSamplesQ8 < 0) {
-                throw new IllegalArgumentException("Hotspot samples must be non-negative");
+            if (measurementStartTick <= 0L || samples < 0L || maxSamplesQ8 < 0) {
+                throw new IllegalArgumentException("Invalid hotspot measurement data");
             }
             key.validateDetailKind(detailKind);
             if (key.kind() == Kind.BLOCK_ENTITY
@@ -69,6 +73,11 @@ public record PerfWorldHotspotIndex(long streamEpoch,
             }
         }
 
+        public long measurementTicks(long totalTicks) {
+            return totalTicks <= 0L ? 0L
+                    : Math.max(1L, totalTicks - measurementStartTick + 1L);
+        }
+
     }
 
     public record Key(Kind kind, int entityId, long blockPosition) {

src/main/java/com/moepus/serverwarashi/common/modules/performance/sampling/PerfObjectSnapshotBuilder.java

@@ -177,7 +177,8 @@ final class PerfObjectSnapshotBuilder {
                                       PerfReportData.Metric metric,
                                       long tickCount) {
             return new ObjectCandidate(key, aggregate, metric,
-                    ObjectPerformanceScale.effectiveSamples(metric, tickCount),
+                    ObjectPerformanceScale.effectiveSamples(
+                            metric, aggregate.measurementTicks(tickCount)),
                     StableObjectId.from(key, aggregate), tickCount);
         }
 
@@ -203,7 +204,7 @@ final class PerfObjectSnapshotBuilder {
             PerfWorldHotspotIndex.Cost cost = aggregate.stats.hotspotCost(tickCount);
             return new PerfWorldHotspotIndex.Entry(hotspotKey(), key.dimension(),
                     aggregate.x, aggregate.y, aggregate.z, key.detailKind(), key.detailId(),
-                    cost.samples(), cost.maxSamplesQ8());
+                    aggregate.measurementStartTick, cost.samples(), cost.maxSamplesQ8());
         }
 
         static ObjectCandidate newer(ObjectCandidate left, ObjectCandidate right) {

src/main/java/com/moepus/serverwarashi/common/modules/performance/sampling/PerfSampleAggregator.java

@@ -251,6 +251,7 @@ final class PerfSampleAggregator {
         boolean chunkPosition;
         int x, y, z;
         long lastSeenTick;
+        long measurementStartTick = 1L;
 
         void record(TickSamples.TickCount count, long tick) {
             positioned = count.positioned;
@@ -259,6 +260,10 @@ final class PerfSampleAggregator {
             y = count.y;
             z = count.z;
             lastSeenTick = tick;
+            if (count.entityAgeTicks >= 0) {
+                long age = Math.max(1L, count.entityAgeTicks);
+                measurementStartTick = Math.max(1L, tick - age + 1L);
+            }
             stats.record(count.count, tick);
         }
 
@@ -283,7 +288,11 @@ final class PerfSampleAggregator {
         }
 
         PerfReportData.Metric metric(long ticks, double nanosPerSample) {
-            return stats.metric(ticks, nanosPerSample);
+            return stats.metric(ticks, measurementTicks(ticks), nanosPerSample);
+        }
+
+        long measurementTicks(long ticks) {
+            return ticks <= 0L ? 0L : Math.max(1L, ticks - measurementStartTick + 1L);
         }
 
         TickSamples.ChunkKey chunkKey(TickSamples.TickableKey key) {

src/main/java/com/moepus/serverwarashi/common/modules/performance/sampling/PerfWorkTracker.java

@@ -174,7 +174,25 @@ public final class PerfWorkTracker {
                            int z,
                            boolean chunkPosition,
                            String eventLoop,
-                           String displayName) {
+                           String displayName,
+                           int entityAgeTicks) {
+        public Snapshot(TickType type,
+                        ResourceLocation dimension,
+                        Class<?> workClass,
+                        ResourceLocation detailId,
+                        TickDetailKind detailKind,
+                        int entityId,
+                        boolean positioned,
+                        int x,
+                        int y,
+                        int z,
+                        boolean chunkPosition,
+                        String eventLoop,
+                        String displayName) {
+            this(type, dimension, workClass, detailId, detailKind, entityId,
+                    positioned, x, y, z, chunkPosition, eventLoop, displayName, -1);
+        }
+
         public Snapshot(TickType type,
                         ResourceLocation dimension,
                         Class<?> workClass,
@@ -188,7 +206,7 @@ public final class PerfWorkTracker {
                         boolean chunkPosition,
                         String eventLoop) {
             this(type, dimension, workClass, detailId, detailKind, entityId,
-                    positioned, x, y, z, chunkPosition, eventLoop, "");
+                    positioned, x, y, z, chunkPosition, eventLoop, "", -1);
         }
     }
 
@@ -208,6 +226,7 @@ public final class PerfWorkTracker {
         private boolean chunkPosition;
         private String eventLoop;
         private String displayName;
+        private int entityAgeTicks;
 
         void publishChunk(ResourceLocation dimension, LevelChunk chunk) {
             var pos = chunk.getPos();
@@ -222,6 +241,7 @@ public final class PerfWorkTracker {
             z = pos.z;
             chunkPosition = true;
             eventLoop = null;
+            entityAgeTicks = -1;
             finishPublish();
         }
 
@@ -242,6 +262,7 @@ public final class PerfWorkTracker {
             z = entity.getBlockZ();
             chunkPosition = false;
             eventLoop = null;
+            entityAgeTicks = Math.max(1, entity.tickCount + 1);
             finishPublish();
         }
 
@@ -258,6 +279,7 @@ public final class PerfWorkTracker {
             z = pos.getZ();
             chunkPosition = false;
             eventLoop = null;
+            entityAgeTicks = -1;
             finishPublish();
         }
 
@@ -273,6 +295,7 @@ public final class PerfWorkTracker {
             z = 0;
             chunkPosition = false;
             this.eventLoop = eventLoop;
+            entityAgeTicks = -1;
             finishPublish();
         }
 
@@ -301,7 +324,7 @@ public final class PerfWorkTracker {
             }
             Snapshot result = new Snapshot(type, dimension, workClass, detailId, detailKind,
                     entityId, positioned,
-                    x, y, z, chunkPosition, eventLoop, displayName);
+                    x, y, z, chunkPosition, eventLoop, displayName, entityAgeTicks);
             return before == version ? result : null;
         }
     }

src/main/java/com/moepus/serverwarashi/common/modules/performance/sampling/SampleStatistics.java

@@ -35,9 +35,14 @@ final class SampleStatistics {
     }
 
     PerfReportData.Metric metric(long totalTicks, double nanosPerSample) {
-        advanceWindows(totalTicks);
-        double mspt = totalTicks == 0 ? 0.0D
-                : totalSamples * nanosPerSample / NANOS_PER_MILLISECOND / totalTicks;
+        return metric(totalTicks, totalTicks, nanosPerSample);
+    }
+
+    PerfReportData.Metric metric(long currentTick, long measurementTicks,
+                                 double nanosPerSample) {
+        advanceWindows(currentTick);
+        double mspt = measurementTicks == 0L ? 0.0D
+                : totalSamples * nanosPerSample / NANOS_PER_MILLISECOND / measurementTicks;
         double estimatedMaxSamples = estimatedMaxSamples();
         double estimatedMax = estimatedMaxSamples * nanosPerSample / NANOS_PER_MILLISECOND;
         return new PerfReportData.Metric(mspt, Math.max(mspt, estimatedMax), Math.round(totalSamples));

src/main/java/com/moepus/serverwarashi/common/modules/performance/sampling/TickSamples.java

@@ -104,6 +104,7 @@ final class TickSamples {
         int x;
         int y;
         int z;
+        int entityAgeTicks = -1;
 
         void record(PerfWorkTracker.Snapshot snapshot) {
             count++;
@@ -112,6 +113,7 @@ final class TickSamples {
             x = snapshot.x();
             y = snapshot.y();
             z = snapshot.z();
+            entityAgeTicks = snapshot.entityAgeTicks();
         }
 
         void merge(TickCount source) {
@@ -121,6 +123,7 @@ final class TickSamples {
             x = source.x;
             y = source.y;
             z = source.z;
+            entityAgeTicks = Math.max(entityAgeTicks, source.entityAgeTicks);
         }
     }
 }

src/main/java/com/moepus/serverwarashi/common/network/PerfWorldHotspotPayload.java

@@ -45,6 +45,9 @@ public record PerfWorldHotspotPayload(long streamEpoch,
         removals = List.copyOf(removals);
         validateSize(upserts.size());
         validateSize(removals.size());
+        if (upserts.stream().anyMatch(entry -> entry.measurementStartTick() > tickCount)) {
+            throw new IllegalArgumentException("Hotspot measurement starts after the payload");
+        }
     }
 
     @Override
@@ -84,6 +87,7 @@ public record PerfWorldHotspotPayload(long streamEpoch,
         writeKey(buffer, entry.key);
         buffer.writeByte(entry.detailKind.ordinal());
         buffer.writeVarInt(entry.registryId);
+        buffer.writeVarLong(entry.measurementStartTick);
         buffer.writeVarLong(entry.samples);
         buffer.writeVarInt(entry.maxSamplesQ8);
     }
@@ -96,7 +100,7 @@ public record PerfWorldHotspotPayload(long streamEpoch,
             throw new IllegalArgumentException("Unknown hotspot detail kind: " + detailOrdinal);
         }
         return new Entry(key, kinds[detailOrdinal], buffer.readVarInt(),
-                buffer.readVarLong(), buffer.readVarInt());
+                buffer.readVarLong(), buffer.readVarLong(), buffer.readVarInt());
     }
 
     private static void writeKey(
@@ -140,12 +144,14 @@ public record PerfWorldHotspotPayload(long streamEpoch,
     public record Entry(PerfWorldHotspotIndex.Key key,
                         TickDetailKind detailKind,
                         int registryId,
+                        long measurementStartTick,
                         long samples,
                         int maxSamplesQ8) {
         public Entry {
             Objects.requireNonNull(key, "key");
             Objects.requireNonNull(detailKind, "detailKind");
-            if (registryId < 0 || samples < 0L || maxSamplesQ8 < 0) {
+            if (registryId < 0 || measurementStartTick <= 0L
+                    || samples < 0L || maxSamplesQ8 < 0) {
                 throw new IllegalArgumentException("Invalid compact hotspot entry");
             }
             key.validateDetailKind(detailKind);

src/main/java/com/moepus/serverwarashi/common/network/PerfWorldHotspotResolver.java

@@ -45,7 +45,8 @@ final class PerfWorldHotspotResolver {
         String dimension = entity.level().dimension().location().toString();
         return new PerfWorldHotspotIndex.Entry(entry.key(), dimension,
                 entity.getBlockX(), entity.getBlockY(), entity.getBlockZ(),
-                entry.detailKind(), entry.detailId(), entry.samples(), entry.maxSamplesQ8());
+                entry.detailKind(), entry.detailId(), entry.measurementStartTick(),
+                entry.samples(), entry.maxSamplesQ8());
     }
 
     private static Entity findEntity(PerfWorldHotspotIndex.Entry entry,

src/main/java/com/moepus/serverwarashi/common/network/PerfWorldHotspotStream.java

@@ -120,7 +120,7 @@ final class PerfWorldHotspotStream {
         int registryId = registryIds.resolve(entry.detailKind(), entry.detailId());
         return registryId < 0 ? null : new PerfWorldHotspotPayload.Entry(
                 entry.key(), entry.detailKind(), registryId,
-                entry.samples(), entry.maxSamplesQ8());
+                entry.measurementStartTick(), entry.samples(), entry.maxSamplesQ8());
     }
 
     private static int builtInRegistryId(TickDetailKind kind, ResourceLocation id) {

src/main/java/com/moepus/serverwarashi/common/network/WarashiNetwork.java

@@ -15,7 +15,7 @@ import net.neoforged.neoforge.network.registration.NetworkRegistry;
 
 @EventBusSubscriber(modid = ServerWarashi.MODID, bus = EventBusSubscriber.Bus.MOD)
 public final class WarashiNetwork {
-    static final String NETWORK_VERSION = "6";
+    static final String NETWORK_VERSION = "7";
 
     private WarashiNetwork() {
     }

src/test/java/com/moepus/serverwarashi/client/state/ClientPerfStateCoordinatorTest.java

@@ -45,7 +45,7 @@ class ClientPerfStateCoordinatorTest {
     void clearAllResetsReportMapAndWorldStores() {
         ClientPerfStateCoordinator.applyFullReport(report(), true);
         var entry = new PerfWorldHotspotPayload.Entry(
-                PerfWorldHotspotIndex.Key.entity(7), TickDetailKind.ENTITY, 1, 2L, 256);
+                PerfWorldHotspotIndex.Key.entity(7), TickDetailKind.ENTITY, 1, 1L, 2L, 256);
         ClientPerfStateCoordinator.applyWorldDelta(new PerfWorldHotspotPayload(
                 1L, 0L, 1L, 20L, 1_000_000L,
                 ResourceLocation.parse("minecraft:overworld"), true,

src/test/java/com/moepus/serverwarashi/client/state/ClientPerfWorldStateTest.java

@@ -26,7 +26,7 @@ class ClientPerfWorldStateTest {
     @Test
     void scalarOnlyDeltaRefreshesMetricWithoutRepeatingEntry() {
         var entry = new PerfWorldHotspotPayload.Entry(
-                KEY, TickDetailKind.ENTITY, 4, 20L, 512);
+                KEY, TickDetailKind.ENTITY, 4, 1L, 20L, 512);
         assertTrue(ClientPerfWorldState.apply(payload(0L, 20L, 20L, 1_000_000L,
                 true, List.of(entry), List.of())));
         assertEquals(1.0D, metric().mspt(), 1.0E-9D);
@@ -40,7 +40,7 @@ class ClientPerfWorldStateTest {
     @Test
     void rejectsDeltaWithWrongBaseAndAppliesRemoval() {
         var entry = new PerfWorldHotspotPayload.Entry(
-                KEY, TickDetailKind.ENTITY, 4, 2L, 256);
+                KEY, TickDetailKind.ENTITY, 4, 1L, 2L, 256);
         ClientPerfWorldState.apply(payload(
                 0L, 20L, 20L, 1_000_000L, true, List.of(entry), List.of()));
         assertFalse(ClientPerfWorldState.apply(payload(
@@ -53,7 +53,7 @@ class ClientPerfWorldStateTest {
     @Test
     void rejectsOlderFullSnapshotButAcceptsANewStreamEpoch() {
         var entry = new PerfWorldHotspotPayload.Entry(
-                KEY, TickDetailKind.ENTITY, 4, 2L, 256);
+                KEY, TickDetailKind.ENTITY, 4, 1L, 2L, 256);
         assertTrue(ClientPerfWorldState.apply(new PerfWorldHotspotPayload(
                 7L, 0L, 20L, 20L, 1_000_000L, DIMENSION,
                 true, List.of(entry), List.of())));
@@ -70,6 +70,18 @@ class ClientPerfWorldStateTest {
         assertEquals(1L, ClientPerfWorldState.snapshot().protocolRevision());
     }
 
+    @Test
+    void dividesEntityCostByTicksSinceItAppeared() {
+        var entry = new PerfWorldHotspotPayload.Entry(
+                KEY, TickDetailKind.ENTITY, 4, 91L, 20L, 512);
+
+        assertTrue(ClientPerfWorldState.apply(payload(
+                0L, 100L, 100L, 1_000_000L, true, List.of(entry), List.of())));
+
+        assertEquals(2.0D, metric().mspt(), 1.0E-9D);
+        assertEquals(10L, ClientPerfWorldState.snapshot().hotspots().get(0).measurementTicks());
+    }
+
     private static com.moepus.serverwarashi.common.modules.performance.report.PerfReportData.Metric metric() {
         return ClientPerfWorldState.snapshot().hotspots().get(0).metric();
     }

src/test/java/com/moepus/serverwarashi/client/world/WorldEntityFlameClustersTest.java

@@ -69,6 +69,20 @@ class WorldEntityFlameClustersTest {
         assertEquals(clustered.z(), single.z(), 0.000_001D);
     }
 
+    @Test
+    void combinesRatesFromMembersWithDifferentMeasurementWindows() {
+        var recent = new WorldEntityFlameClusters.Input(
+                bounds(new Point(0.0D, 0.0D)), metric(1.0D, 1.0D, 10L), 10L, 1);
+        var old = new WorldEntityFlameClusters.Input(
+                bounds(new Point(0.2D, 0.0D)), metric(1.0D, 1.0D, 100L), 100L, 2);
+
+        WorldEntityFlameClusters.Marker marker =
+                WorldEntityFlameClusters.cluster(List.of(recent, old), 100L).get(0);
+
+        assertEquals(2.0D, marker.metric().mspt(), 0.000_001D);
+        assertEquals(2.0D, marker.effectiveSamples(), 0.000_001D);
+    }
+
     @Test
     void clustersTheMaximumCoincidentInputBudgetWithoutPairMaterialization() {
         List<WorldEntityFlameClusters.Input> inputs = new ArrayList<>();
@@ -85,10 +99,12 @@ class WorldEntityFlameClustersTest {
 
     private static WorldEntityFlameClusters.Input input(
             int id, Point point, PerfReportData.Metric metric) {
-        return new WorldEntityFlameClusters.Input(
-                new AABB(point.x() - 0.3D, 64.0D, point.z() - 0.3D,
-                        point.x() + 0.3D, 65.8D, point.z() + 0.3D),
-                metric, id);
+        return new WorldEntityFlameClusters.Input(bounds(point), metric, id);
+    }
+
+    private static AABB bounds(Point point) {
+        return new AABB(point.x() - 0.3D, 64.0D, point.z() - 0.3D,
+                point.x() + 0.3D, 65.8D, point.z() + 0.3D);
     }
 
     private static WorldEntityFlameClusters.Input input(int id, AABB bounds) {

src/test/java/com/moepus/serverwarashi/common/modules/performance/sampling/PerfSampleAggregatorTest.java

@@ -124,6 +124,35 @@ class PerfSampleAggregatorTest {
         assertTrue(report.chunks().isEmpty());
     }
 
+    @Test
+    void limitsEntityAverageToItsLifetimeInsideTheSamplingSession() {
+        PerfSampleAggregator aggregator = new PerfSampleAggregator(23L);
+        for (int tick = 1; tick <= 90; tick++) {
+            aggregator.accept(new TickSamples(null));
+        }
+        TickSamples spawned = new TickSamples(null);
+        spawned.sample(new PerfWorkTracker.Snapshot(TickType.ENTITY,
+                ResourceLocation.parse("test:level"), Cow.class,
+                ResourceLocation.parse("minecraft:cow"), TickDetailKind.ENTITY, 7,
+                true, 8, 64, 8, false, null, "", 1));
+        aggregator.accept(spawned);
+        for (int tick = 92; tick <= 100; tick++) {
+            aggregator.accept(new TickSamples(null));
+        }
+
+        PerfSampleAggregator.BuildSnapshot build =
+                aggregator.buildSnapshot(milliseconds(100L), 1L, 1_000);
+        double sampleMillis = observedMillis(100L, 1);
+        PerfReportData.TickableEntry entity = build.report().tickables().get(0);
+        PerfWorldHotspotIndex.Entry hotspot = build.hotspots().entries().get(0);
+
+        assertEquals(sampleMillis / 10.0D, entity.metric().mspt(), 0.000_001D);
+        assertEquals(sampleMillis / 100.0D,
+                build.report().chunks().get(0).metric().mspt(), 0.000_001D);
+        assertEquals(91L, hotspot.measurementStartTick());
+        assertEquals(10L, hotspot.measurementTicks(build.hotspots().tickCount()));
+    }
+
     @Test
     void capturesRareMultiSampleEntityTickAsBurstMax() {
         PerfSampleAggregator aggregator = new PerfSampleAggregator(8L);

src/test/java/com/moepus/serverwarashi/common/network/PerfWorldHotspotPayloadTest.java

@@ -18,10 +18,11 @@ class PerfWorldHotspotPayloadTest {
     @Test
     void roundTripsCompactEntriesWithoutUuidIdentity() {
         var entity = new PerfWorldHotspotPayload.Entry(
-                PerfWorldHotspotIndex.Key.entity(42), TickDetailKind.ENTITY, 7, 123L, 640);
+                PerfWorldHotspotIndex.Key.entity(42), TickDetailKind.ENTITY,
+                7, 17L, 123L, 640);
         var blockEntity = new PerfWorldHotspotPayload.Entry(
                 PerfWorldHotspotIndex.Key.blockEntity(3, 64, -2),
-                TickDetailKind.BLOCK, 11, 9L, 384);
+                TickDetailKind.BLOCK, 11, 1L, 9L, 384);
         var expected = new PerfWorldHotspotPayload(5L, 0L, 20L, 20L, 1_250_000L,
                 ResourceLocation.parse("minecraft:overworld"), true,
                 List.of(entity, blockEntity), List.of());
@@ -65,16 +66,16 @@ class PerfWorldHotspotPayloadTest {
 
         assertThrows(IllegalArgumentException.class, () ->
                 new PerfWorldHotspotIndex.Entry(blockKey, "minecraft:overworld",
-                        4, 64, -2, TickDetailKind.BLOCK, stone, 1L, 256));
+                        4, 64, -2, TickDetailKind.BLOCK, stone, 1L, 1L, 256));
         assertThrows(IllegalArgumentException.class, () ->
                 new PerfWorldHotspotIndex.Entry(blockKey, "minecraft:overworld",
-                        3, 64, -2, TickDetailKind.ENTITY, stone, 1L, 256));
+                        3, 64, -2, TickDetailKind.ENTITY, stone, 1L, 1L, 256));
         assertThrows(IllegalArgumentException.class, () ->
                 new PerfWorldHotspotPayload.Entry(
-                        blockKey, TickDetailKind.ENTITY, 1, 1L, 256));
+                        blockKey, TickDetailKind.ENTITY, 1, 1L, 1L, 256));
         assertThrows(IllegalArgumentException.class, () ->
                 new PerfWorldHotspotPayload.Entry(
                         PerfWorldHotspotIndex.Key.entity(4),
-                        TickDetailKind.BLOCK, 1, 1L, 256));
+                        TickDetailKind.BLOCK, 1, 1L, 1L, 256));
     }
 }

src/test/java/com/moepus/serverwarashi/common/network/PerfWorldHotspotStreamTest.java

@@ -122,6 +122,6 @@ class PerfWorldHotspotStreamTest {
             int x, int y, int z, long samples, ResourceLocation detailId) {
         return new PerfWorldHotspotIndex.Entry(
                 PerfWorldHotspotIndex.Key.blockEntity(x, y, z), DIMENSION.toString(), x, y, z,
-                TickDetailKind.BLOCK, detailId, samples, (int) samples * 256);
+                TickDetailKind.BLOCK, detailId, 1L, samples, (int) samples * 256);
     }
 }

src/test/java/com/moepus/serverwarashi/common/network/WeakChunkPayloadTest.java

@@ -77,7 +77,7 @@ class WeakChunkPayloadTest {
 
     @Test
     void networkProtocolIsVersionSix() {
-        assertEquals("6", WarashiNetwork.NETWORK_VERSION);
+        assertEquals("7", WarashiNetwork.NETWORK_VERSION);
     }
 
     private static RegistryFriendlyByteBuf buffer() {