private boolean cleanupClientThreads(ClientProxyMembershipID proxyID, boolean timedOut,
      Throwable reason) {
    boolean result = false;
    Set<ServerConnection> serverConnections = null;
    synchronized (proxyIdConnections) {
      ServerConnectionCollection collection = proxyIdConnections.remove(proxyID);
      if (collection != null) {
        serverConnections = collection.getConnections();
      }
    }
    {
      if (serverConnections != null) {
        result = true;
        for (ServerConnection serverConnection : serverConnections) {
          if (reason != null) {
            serverConnection.setClientDisconnectedException(reason);
          }
          serverConnection.handleTermination(timedOut);
        }
      }
    }
    return result;
  }
This method returns the CacheClientStatus for all the clients that are connected to this
server. This method returns all clients irrespective of whether subscription is enabled or not.

@return Map of ClientProxyMembershipID against CacheClientStatus objects.
geode-core/src/main/java/org/apache/geode/internal/cache/tier/sockets/ClientHealthMonitor.java