Mempool - zoobc/zoobc-core GitHub Wiki

Mempool is pool of pending transactions posted by users to the core node. It's a waiting queue of transactions until block creation event happen.

No	Field	Type	Note
0	id	Int64
1	fee_per_byte	Int64
2	arrival_timestamp	Int64
3	transaction_bytes	[]Byte
4	sender_account_address	[]Byte	*extra
5	recipient_account_address	[]Byte	*extra
6	block_height	Uint32

*extra: sender and recipient information are already in transaction_bytes, but having duplicated those information help in querying the pending transactions from user perspective.

On block creation transaction that the node wants to include to the block will be selected from this table, parse the transaction_bytes to Transaction object, and cast into its Transaction Type.

Basic Rules

There are a few basic rules applied to (default) transaction selection from mempool.

• Expiration

  Node check for transaction expiration (1 hour) from arrival timestamp to selection time.

• Transaction Validity

  Node parse and cast the transaction_bytes and validate that it's a valid transaction, this will keep the node away from broadcasting false transactions.

• Skip Mempool (Transaction-Type Implementation)

  Every transaction type will be able to implement a custom SkipMempoolTransaction() method to flag if transaction can be included in mempool selection or vice-versa. This allow for complex inter-transactionType restriction implementation.

  TODO: ADD_EXAMPLE