Priority fee
A per-compute-unit fee added to a Solana transaction to incentivize validators to include it sooner.
Solana validators schedule transactions partly by the priority fee they include — measured in micro-lamports per compute unit. Higher priority fees push a transaction earlier in the block and improve landing odds during congestion. Priority fees are separate from Jito tips: priority fees go to the validator producing the block, while Jito tips go specifically to validators running the Jito client.
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