From 03c3650cd5d57aa9144415976206494fc94582ac Mon Sep 17 00:00:00 2001
From: Bryan Beaudreault <bbeaudreault@hubspot.com>
Date: Sat, 5 Feb 2022 14:06:16 -0500
Subject: [PATCH] Propagate config changes if balancer is a
 ConfigurationObserver

---
 .../hbase/ipc/BalancedQueueRpcExecutor.java       | 10 ++++++++++
 .../hadoop/hbase/ipc/RWQueueRpcExecutor.java      | 15 +++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/BalancedQueueRpcExecutor.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/BalancedQueueRpcExecutor.java
index cf4c35d7ae1a..ad1747ba3b1f 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/BalancedQueueRpcExecutor.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/BalancedQueueRpcExecutor.java
@@ -21,6 +21,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
+import org.apache.hadoop.hbase.conf.ConfigurationObserver;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
 
@@ -60,4 +61,13 @@ public boolean dispatch(final CallRunner callTask) throws InterruptedException {
     }
     return queue.offer(callTask);
   }
+
+  @Override
+  public void onConfigurationChange(Configuration conf) {
+    super.onConfigurationChange(conf);
+
+    if (balancer instanceof ConfigurationObserver) {
+      ((ConfigurationObserver) balancer).onConfigurationChange(conf);
+    }
+  }
 }
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RWQueueRpcExecutor.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RWQueueRpcExecutor.java
index 450ac29b6a84..b2df2254130a 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RWQueueRpcExecutor.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RWQueueRpcExecutor.java
@@ -25,6 +25,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
+import org.apache.hadoop.hbase.conf.ConfigurationObserver;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
 import org.slf4j.Logger;
@@ -280,4 +281,18 @@ private static int calcNumWriters(final int count, final float readShare) {
   private static int calcNumReaders(final int count, final float readShare) {
     return count - calcNumWriters(count, readShare);
   }
+
+  @Override
+  public void onConfigurationChange(Configuration conf) {
+    super.onConfigurationChange(conf);
+    propagateBalancerConfigChange(writeBalancer, conf);
+    propagateBalancerConfigChange(readBalancer, conf);
+    propagateBalancerConfigChange(scanBalancer, conf);
+  }
+
+  private void propagateBalancerConfigChange(QueueBalancer balancer, Configuration conf) {
+    if (balancer instanceof ConfigurationObserver) {
+      ((ConfigurationObserver) balancer).onConfigurationChange(conf);
+    }
+  }
 }