diff --git a/solr/CHANGES.txt b/solr/CHANGES.txt
index be5eb556f9c..3e8de72b190 100644
--- a/solr/CHANGES.txt
+++ b/solr/CHANGES.txt
@@ -110,7 +110,8 @@ Improvements
 
 Optimizations
 ---------------------
-(No changes)
+* SOLR-17084: LBSolrClient (used by CloudSolrClient) now returns the count of core tracked as not live AKA zombies
+  instead of the full list of cores. This list is potentially VERY long which was causing high CPU and memory usage.
 
 Bug Fixes
 ---------------------
diff --git a/solr/solrj/src/java/org/apache/solr/client/solrj/impl/LBSolrClient.java b/solr/solrj/src/java/org/apache/solr/client/solrj/impl/LBSolrClient.java
index 50841ba2e7e..2723465b739 100644
--- a/solr/solrj/src/java/org/apache/solr/client/solrj/impl/LBSolrClient.java
+++ b/solr/solrj/src/java/org/apache/solr/client/solrj/impl/LBSolrClient.java
@@ -358,7 +358,10 @@ public Rsp request(Req req) throws SolrServerException, IOException {
       }
     }
     throw new SolrServerException(
-        "No live SolrServers available to handle this request:" + zombieServers.keySet(), ex);
+        "No live SolrServers available to handle this request. (Tracking "
+            + zombieServers.size()
+            + " not live)",
+        ex);
   }
 
   /**