public void close() {
        deleteAllSessions();
        tenantFileSystemDirs.delete();
        try {
            if (directoryCache != null) {
                directoryCache.close();
            }
        } catch (Exception e) {
            log.log(Level.WARNING, "Exception when closing path cache", e);
        } finally {
            checkForRemovedSessions(new ArrayList<>());
        }
    }
Create a new local session for the given session id if it does not already exist and
will add the session to the local session cache. If there is no remote session matching
the session id the remote session will also be created.
configserver/src/main/java/com/yahoo/vespa/config/server/session/SessionRepository.java