Set max number of copycat transport server threads to 4

Change-Id: I20c662fdfcabd86b547c7b699b5f97ce3d912a41
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/CopycatTransportServer.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/CopycatTransportServer.java
index 2f24d6b..d4f851f 100644
--- a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/CopycatTransportServer.java
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/CopycatTransportServer.java
@@ -64,7 +64,7 @@
         this.messagingService = checkNotNull(messagingService);
         this.protocolMessageSubject = String.format("onos-copycat-server-%s", partitionId);
         this.newConnectionMessageSubject = String.format("onos-copycat-server-connection-%s", partitionId);
-        this.executorService = Executors.newScheduledThreadPool(Runtime.getRuntime().availableProcessors(),
+        this.executorService = Executors.newScheduledThreadPool(Math.min(4, Runtime.getRuntime().availableProcessors()),
                 new CatalystThreadFactory("copycat-server-p" + partitionId + "-%d"));
     }