diff --git a/core/src/test/scala/akka/persistence/jdbc/query/CurrentEventsByTagTest.scala b/core/src/test/scala/akka/persistence/jdbc/query/CurrentEventsByTagTest.scala
index f84e97c2..baa92094 100644
--- a/core/src/test/scala/akka/persistence/jdbc/query/CurrentEventsByTagTest.scala
+++ b/core/src/test/scala/akka/persistence/jdbc/query/CurrentEventsByTagTest.scala
@@ -16,6 +16,8 @@ import akka.persistence.jdbc.query.EventAdapterTest.{ Event, TaggedAsyncEvent }
 import scala.concurrent.Future
 import CurrentEventsByTagTest._
 
+import java.util.concurrent.CountDownLatch
+
 object CurrentEventsByTagTest {
   val maxBufferSize = 20
   val refreshInterval = 500.milliseconds
@@ -168,11 +170,16 @@ abstract class CurrentEventsByTagTest(config: String) extends QueryTestSpec(conf
   it should "complete without any gaps in case events are being persisted when the query is executed" in withActorSystem {
     implicit system =>
 
+      val latch = new CountDownLatch(1)
       val journalOps = new JavaDslJdbcReadJournalOperations(system)
       import system.dispatcher
       withTestActors(replyToMessages = true) { (actor1, actor2, actor3) =>
         def sendMessagesWithTag(tag: String, numberOfMessagesPerActor: Int): Future[Done] = {
           val futures = for (actor <- Seq(actor1, actor2, actor3); i <- 1 to numberOfMessagesPerActor) yield {
+            // block the execution
+            if (i == numberOfMessagesPerActor / 2) {
+              latch.await()
+            }
             actor ? TaggedAsyncEvent(Event(i.toString), tag)
           }
           Future.sequence(futures).map(_ => Done)
@@ -182,7 +189,7 @@ abstract class CurrentEventsByTagTest(config: String) extends QueryTestSpec(conf
         // send a batch of 3 * 200
         val batch1 = sendMessagesWithTag(tag, 200)
         // Try to persist a large batch of events per actor. Some of these may be returned, but not all!
-        val batch2 = sendMessagesWithTag(tag, 3000)
+        val batch2 = sendMessagesWithTag(tag, 2000)
 
         // wait for acknowledgement of the first batch only
         batch1.futureValue
@@ -191,6 +198,8 @@ abstract class CurrentEventsByTagTest(config: String) extends QueryTestSpec(conf
 
         // start the query before the last batch completes
         journalOps.withCurrentEventsByTag()(tag, NoOffset) { tp =>
+          // when query begin running, unlock the barrier.
+          latch.countDown()
           // The stream must complete within the given amount of time
           // This make take a while in case the journal sequence actor detects gaps
           val allEvents = tp.toStrict(atMost = 20.seconds)