IGNITE-28832 Fix flaky StatisticsConfigurationTest.updateStatisticsOnChangeTopology

modules/indexing/src/test/java/org/apache/ignite/internal/processors/query/stat/StatisticsConfigurationTest.java

@@ -31,6 +31,7 @@
 import org.apache.ignite.configuration.IgniteConfiguration;
 import org.apache.ignite.internal.IgniteEx;
 import org.apache.ignite.internal.IgniteInterruptedCheckedException;
+import org.apache.ignite.internal.processors.cache.distributed.dht.preloader.GridDhtPartitionDemander;
 import org.apache.ignite.internal.processors.cache.persistence.IgniteCacheDatabaseSharedManager;
 import org.apache.ignite.internal.processors.query.stat.config.StatisticsObjectConfiguration;
 import org.apache.ignite.internal.processors.query.stat.messages.StatisticsObjectData;
@@ -135,6 +136,11 @@ public static List<Object[]> parameters() {
         cleanPersistenceDir();
     }
 
+    /** {@inheritDoc} */
+    @Override protected long getPartitionMapExchangeTimeout() {
+        return super.getPartitionMapExchangeTimeout() * 3;
+    }
+
     /** */
     protected IgniteEx startGridAndChangeBaseline(int nodeIdx) throws Exception {
         IgniteEx ign = startGrid(nodeIdx);
@@ -150,12 +156,35 @@ protected IgniteEx startGridAndChangeBaseline(int nodeIdx) throws Exception {
     }
 
     /** */
-    protected void stopGridAndChangeBaseline(int nodeIdx) {
+    protected void stopGridAndChangeBaseline(int nodeIdx) throws Exception {
         stopGrid(nodeIdx);
 
-        if (persist)
+        if (persist) {
             F.first(G.allGrids()).cluster().setBaselineTopology(F.first(G.allGrids()).cluster().topologyVersion());
 
+            // Wait for rebalancing to finish on all nodes after baseline change.
+            // setBaselineTopology triggers a full exchange with async rebalancing.
+            // awaitPartitionMapExchange checks ownerNodesCnt against readyAffinityVersion,
+            // but partition topology (MOVING) lags behind — causing infinite loop and timeout.
+            // We wait for the rebalance future to complete (blocking.get()) before proceeding.
+            for (Ignite grid : G.allGrids()) {
+                IgniteEx ign = (IgniteEx)grid;
+
+                if (ign.cluster().localNode().isClient())
+                    continue;
+
+                // Wait for ongoing rebalance to complete.
+                GridDhtPartitionDemander.RebalanceFuture rebFut = (GridDhtPartitionDemander.RebalanceFuture)ign
+                    .cachex("SMALLnull").context().preloader().rebalanceFuture();
+
+                // If rebalance was cancelled (false), a new one may have started — retry.
+                while (!rebFut.isInitial() && !rebFut.get()) {
+                    rebFut = (GridDhtPartitionDemander.RebalanceFuture)ign.cachex("SMALLnull")
+                        .context().preloader().rebalanceFuture();
+                }
+            }
+        }
+
         try {
             awaitPartitionMapExchange();
         }