From 35e4e30ecdad9c37eae086e73e9fc443344172b4 Mon Sep 17 00:00:00 2001
From: Brian Neumann-Fopiano <mypsn1550@gmail.com>
Date: Wed, 21 Oct 2026 21:58:31 -0400
Subject: [PATCH] Performance core pools

- Generation pool sized to performance cores
- Pregen burst raise sized from performance cores
- Hydrology planner pool sized to performance cores, at least four
---
 .../iris/generation/concurrent/MultiBurst.java      | 13 ++++++++++---
 .../iris/world/pregen/PregenPerformanceProfile.java |  7 ++++---
 .../generation/concurrent/HydrologyBurstTest.java   |  8 ++++++++
 .../world/pregen/PregenPerformanceProfileTest.java  |  2 +-
 4 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/core/src/main/java/art/arcane/iris/generation/concurrent/MultiBurst.java b/core/src/main/java/art/arcane/iris/generation/concurrent/MultiBurst.java
index 0969ba03d..66fe2961c 100644
--- a/core/src/main/java/art/arcane/iris/generation/concurrent/MultiBurst.java
+++ b/core/src/main/java/art/arcane/iris/generation/concurrent/MultiBurst.java
@@ -26,7 +26,7 @@ public class MultiBurst extends MultiBurstSupport {
     private final AtomicInteger parallelismBaseline = new AtomicInteger();
 
     public MultiBurst() {
-        this("Iris");
+        this("Iris", Thread.MIN_PRIORITY, MultiBurstSupport::performanceProcessors);
     }
 
     public MultiBurst(String name) {
@@ -140,8 +140,15 @@ public class MultiBurst extends MultiBurstSupport {
 
     static final class HydrologyBurst extends MultiBurst {
         HydrologyBurst() {
-            super("Iris Hydrology", () -> Math.max(2,
-                    IrisSettings.getThreadCount(IrisSettings.get().getConcurrency().getParallelism())));
+            super("Iris Hydrology", HydrologyBurst::plannerParallelism);
+        }
+
+        static int plannerParallelism() {
+            return plannerParallelism(MultiBurstSupport.performanceProcessors());
+        }
+
+        static int plannerParallelism(int performanceProcessors) {
+            return Math.max(4, performanceProcessors);
         }
 
         @Override
diff --git a/core/src/main/java/art/arcane/iris/world/pregen/PregenPerformanceProfile.java b/core/src/main/java/art/arcane/iris/world/pregen/PregenPerformanceProfile.java
index c5d5b10b2..3fc3c3b2c 100644
--- a/core/src/main/java/art/arcane/iris/world/pregen/PregenPerformanceProfile.java
+++ b/core/src/main/java/art/arcane/iris/world/pregen/PregenPerformanceProfile.java
@@ -24,6 +24,7 @@ import art.arcane.iris.generation.runtime.Engine;
 import art.arcane.iris.platform.generation.PlatformChunkGenerator;
 import art.arcane.iris.spi.IrisLogging;
 import art.arcane.iris.generation.concurrent.MultiBurst;
+import art.arcane.volmlib.util.parallel.MultiBurstSupport;
 
 import java.util.Objects;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -45,7 +46,7 @@ public final class PregenPerformanceProfile {
             changed = true;
         }
 
-        if (MultiBurst.burst.raiseParallelism(pregenBurstParallelism(Runtime.getRuntime().availableProcessors()))) {
+        if (MultiBurst.burst.raiseParallelism(pregenBurstParallelism(MultiBurstSupport.performanceProcessors()))) {
             PARALLELISM_HOLDERS.incrementAndGet();
             changed = true;
         }
@@ -88,8 +89,8 @@ public final class PregenPerformanceProfile {
         apply(generator == null ? null : generator.getEngine());
     }
 
-    static int pregenBurstParallelism(int availableProcessors) {
-        return Math.max(4, availableProcessors * 2);
+    static int pregenBurstParallelism(int performanceProcessors) {
+        return Math.max(4, performanceProcessors * 2);
     }
 
     private static void prepareNoiseCacheInPlace(Engine engine) {
diff --git a/core/src/test/java/art/arcane/iris/generation/concurrent/HydrologyBurstTest.java b/core/src/test/java/art/arcane/iris/generation/concurrent/HydrologyBurstTest.java
index 7aa6ababd..bd0aca932 100644
--- a/core/src/test/java/art/arcane/iris/generation/concurrent/HydrologyBurstTest.java
+++ b/core/src/test/java/art/arcane/iris/generation/concurrent/HydrologyBurstTest.java
@@ -12,6 +12,7 @@ import java.util.concurrent.ForkJoinTask;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotSame;
 import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
@@ -60,6 +61,13 @@ public class HydrologyBurstTest {
         assertTrue(pool.isTerminated());
     }
 
+    @Test
+    public void plannerPoolFollowsThePerformanceCores() {
+        assertEquals(12, MultiBurst.HydrologyBurst.plannerParallelism(12));
+        assertEquals(4, MultiBurst.HydrologyBurst.plannerParallelism(1));
+        assertEquals(32, MultiBurst.HydrologyBurst.plannerParallelism(32));
+    }
+
     @Test
     public void closedHydrologyWorkersTerminateAndReopenCreatesANewPool() throws Exception {
         IrisSettings previousSettings = IrisSettings.settings;
diff --git a/core/src/test/java/art/arcane/iris/world/pregen/PregenPerformanceProfileTest.java b/core/src/test/java/art/arcane/iris/world/pregen/PregenPerformanceProfileTest.java
index 96c0e407f..21f574cc0 100644
--- a/core/src/test/java/art/arcane/iris/world/pregen/PregenPerformanceProfileTest.java
+++ b/core/src/test/java/art/arcane/iris/world/pregen/PregenPerformanceProfileTest.java
@@ -99,7 +99,7 @@ public class PregenPerformanceProfileTest {
     }
 
     @Test
-    public void pregenerationWantsTwoBurstWorkersPerCore() {
+    public void pregenerationWantsTwoBurstWorkersPerPerformanceCore() {
         assertEquals(32, PregenPerformanceProfile.pregenBurstParallelism(16));
         assertEquals(4, PregenPerformanceProfile.pregenBurstParallelism(1));
     }