SOLR-10370: ReplicationHandler should fetch index at fixed delay instead of fixed rate

solr/CHANGES.txt

@@ -130,6 +130,8 @@ Other Changes
 
 * SOLR-14829: Cleanup the documentation for Request Handlers and Search Components (Alexandre Rafalovitch)
 
+* SOLR-10370: ReplicationHandler should fetch index at fixed delay instead of fixed rate (Cao Manh Dat)
+
 Bug Fixes
 ---------------------
 * SOLR-14546: Fix for a relatively hard to hit issue in OverseerTaskProcessor that could lead to out of order execution

solr/core/src/java/org/apache/solr/handler/ReplicationHandler.java

@@ -1217,7 +1217,7 @@ public class ReplicationHandler extends RequestHandlerBase implements SolrCoreAw
     // Randomize initial delay, with a minimum of 1ms
     long initialDelayNs = new Random().nextLong() % pollIntervalNs
         + TimeUnit.NANOSECONDS.convert(1, TimeUnit.MILLISECONDS);
-    executorService.scheduleAtFixedRate(task, initialDelayNs, pollIntervalNs, TimeUnit.NANOSECONDS);
+    executorService.scheduleWithFixedDelay(task, initialDelayNs, pollIntervalNs, TimeUnit.NANOSECONDS);
     log.info("Poll scheduled at an interval of {}ms",
         TimeUnit.MILLISECONDS.convert(pollIntervalNs, TimeUnit.NANOSECONDS));
   }