public CompletableFuture<Void> setDisabled() {
    if (isEnabled()) {
      isPoolEnabled.set(false);
      subscribeConnectId.ifPresent(ethContext.getEthPeers()::unsubscribeConnect);
      pendingTransactionsListenersProxy.unsubscribe();
      final CompletableFuture<Void> saveOperation =
          saveRestoreManager
              .saveToDisk(pendingTransactions)
              .exceptionally(
                  t -> {
                    LOG.error("Error while saving transaction pool to disk", t);
                    return null;
                  });
      pendingTransactions = new DisabledPendingTransactions();
      return saveOperation;
    }
    return CompletableFuture.completedFuture(null);
  }
Maintains the set of pending transactions received from JSON-RPC or other nodes. Transactions are
removed automatically when they are included in a block on the canonical chain and re-added if a
re-org removes them from the canonical chain again.

<p>This class is safe for use across multiple threads.
ethereum/eth/src/main/java/org/hyperledger/besu/ethereum/eth/transactions/TransactionPool.java