backupManager - backup on all nodes and slowly

[Ja kub]

With below BackupManager backup manager configuration in server.xml
heap memory increases over 100MB on each of four nodes in cluster.

In addition time of
ab -c 10 -n 100000 -p post.txt http://localhost:18080/petclinic/session/fill
is about 150 seconds
with default DeltaManager it is about 15 seconds.

<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"
channelSendOptions="6">

                  <Manager
className="org.apache.catalina.ha.session.BackupManager"
                   expireSessionsOnShutdown="false"
                   notifyListenersOnReplication="true"
                   mapSendOptions="6"/>

</Cluster>


What may I be doing wrong ?

BR
Jakub