BZ2117868: Add a note

Author: xenolinux

networking/ovn_kubernetes_network_provider/tracking-network-flows.adoc

@@ -33,6 +33,11 @@ When OVS sends data to the collectors, each type of collector receives identical
 
 Collecting the network flows data and sending the records to collectors affects performance. Nodes process packets at a slower rate. If the performance impact is too great, you can delete the destinations for collectors to disable collecting network flows data and restore performance.
 
+[NOTE]
+====
+Enabling network flow collectors might have an impact on the overall performance of the cluster network.
+====
+
 include::modules/nw-network-flows-object.adoc[leveloffset=+1]
 
 include::modules/nw-network-flows-create.adoc[leveloffset=+1]