Optimism has a transaction pool and supports EIP 1559. The transaction pool is private, so your transactions are not shared with anybody until they are actually included in a block.
The transaction pool affects users in two ways:
- You can specify a high priority fee to make it more likely that your transaction is included early in the next block.
- If a transaction's L2 gas price is so low, it can stay stuck. In that case, you can cancel it by submitting another transaction with the same nonce. You can also submit the exact same transaction, with the same nonce, and only a higher gas price.