private void saveTXStateForClientFailover(TXStateProxy tx, TXCommitMessage msg) {
    if (tx.isOnBehalfOfClient() && tx.isRealDealLocal()) {
      failoverMap.put(tx.getTxId(), msg);
      if (logger.isDebugEnabled()) {
        logger.debug(
            "TX: storing client initiated transaction:{}; now there are {} entries in the failoverMap",
            tx.getTxId(), failoverMap.size());
      }
    }
  }
This method is only being invoked by pre geode 1.7.0 server during rolling upgrade now.
The remote server has waited for transactionTimeToLive and require this server to
remove the client transactions. Need to check if there is no activity of the client
transaction.
geode-core/src/main/java/org/apache/geode/internal/cache/TXManagerImpl.java