How Does a Validator Choose Which Transactions to Include in a Block?

A validator chooses transactions from the mempool based on a strategy that maximizes their profit, subject to the block's gas limit. Under EIP-1559, they prioritize transactions that offer the highest priority fee (tip) and may also consider the total transaction value if they are involved in MEV extraction.

In the Proof-of-Stake system with Proposer-Builder Separation (PBS), the validator's choice is often simplified to selecting the most profitable block header submitted by a block builder.

How Does the ‘EIP-1559’ Upgrade Affect Ethereum’s Transaction Fee Structure?
How Does the “Base Fee” and “Priority Fee” System Work under EIP-1559?
What Is the Difference between a ‘Priority Fee’ and a ‘Base Fee’?
How Do Competing Mining Pools Influence the Average Transaction Fee?
Explain How “Priority Fees” (Tips) Are Used in Modern Blockchain Fee Markets
How Has Ethereum’s EIP-1559 Changed the Dynamics of Gas Fee Bidding?
What Is the Concept of a ‘Tip’ or ‘Priority Fee’ in Modern Blockchain Transaction Models?
What Is the “Priority Fee” and Why Is It Still Necessary with EIP-1559?

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