@Override
  public boolean equals(final Object o) {
    if (this == o) {
      return true;
    }
    if (o == null || getClass() != o.getClass()) {
      return false;
    }
    TransactionSelectionResults that = (TransactionSelectionResults) o;
    return cumulativeGasUsed == that.cumulativeGasUsed
        && selectedTransactions.equals(that.selectedTransactions)
        && notSelectedTransactions.equals(that.notSelectedTransactions)
        && receipts.equals(that.receipts);
  }
Access to this field needs to be guarded, since it is possible to read it while another
processing thread is writing, when the selection time is over.
ethereum/blockcreation/src/main/java/org/hyperledger/besu/ethereum/blockcreation/txselection/TransactionSelectionResults.java