From ef5047d64c9409e68b6b6ff20cbd1afb8ecf0191 Mon Sep 17 00:00:00 2001
From: Matt Jacobs <mjacobs@netflix.com>
Date: Thu, 10 Nov 2016 13:50:35 -0800
Subject: [PATCH] When user has not opted in to letting core/maximum
 threadpools diverge, ensure dynamic updates to coreSize apply to both

---
 .../main/java/com/netflix/hystrix/HystrixThreadPool.java    | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/hystrix-core/src/main/java/com/netflix/hystrix/HystrixThreadPool.java b/hystrix-core/src/main/java/com/netflix/hystrix/HystrixThreadPool.java
index e812b46ee..26c7a3109 100644
--- a/hystrix-core/src/main/java/com/netflix/hystrix/HystrixThreadPool.java
+++ b/hystrix-core/src/main/java/com/netflix/hystrix/HystrixThreadPool.java
@@ -221,10 +221,16 @@ private void touchConfig() {
             boolean maxTooLow = false;
 
             if (allowSizesToDiverge && dynamicMaximumSize < dynamicCoreSize) {
+                //if user sets maximum < core (or defaults get us there), we need to maintain invariant of core <= maximum
                 dynamicMaximumSize = dynamicCoreSize;
                 maxTooLow = true;
             }
 
+            if (!allowSizesToDiverge) {
+                //if user has not opted in to allowing sizes to diverge, ensure maximum == core
+                dynamicMaximumSize = dynamicCoreSize;
+            }
+
             // In JDK 6, setCorePoolSize and setMaximumPoolSize will execute a lock operation. Avoid them if the pool size is not changed.
             if (threadPool.getCorePoolSize() != dynamicCoreSize || (allowSizesToDiverge && threadPool.getMaximumPoolSize() != dynamicMaximumSize)) {
                 if (maxTooLow) {