Randomise nodes shards iterator for move

Signed-off-by: Rishab Nahata <rnnahata@amazon.com>
imRishN · Aug 15, 2024 · 7fe10d7 · 7fe10d7
1 parent 0e9151c
commit 7fe10d7
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/server/src/main/java/org/opensearch/cluster/routing/RoutingNodes.java b/server/src/main/java/org/opensearch/cluster/routing/RoutingNodes.java
@@ -1439,7 +1439,9 @@ public void remove() {
      */
     public Iterator<ShardRouting> nodeInterleavedShardIterator(ShardMovementStrategy shardMovementStrategy) {
         final Queue<Iterator<ShardRouting>> queue = new ArrayDeque<>();
-        for (Map.Entry<String, RoutingNode> entry : nodesToShards.entrySet()) {
+        List<Map.Entry<String, RoutingNode>> nodesToShardsEntrySet = new ArrayList<>(nodesToShards.entrySet());
+        Randomness.shuffle(nodesToShardsEntrySet);
+        for (Map.Entry<String, RoutingNode> entry : nodesToShardsEntrySet) {
             queue.add(entry.getValue().copyShards().iterator());
         }
         if (shardMovementStrategy == ShardMovementStrategy.PRIMARY_FIRST) {