A measure of computational resources consumed by transaction execution, analogous to gas on Ethereum. Each BPF instruction costs CU; syscalls have predefined CU costs (e.g., SHA-256: 85 CU base + per-byte). Default per-instruction limit is 200,000 CU; max per-transaction is 1,400,000 CU. Priority fee cost = CU price × CU consumed.
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A measure of computational resources consumed by transaction execution, analogous to gas on Ethereum. Each BPF instruction costs CU; syscalls have predefined CU costs (e.g., SHA-256: 85 CU base + per-byte). Default per-instruction limit is 200,000 CU; max per-transaction is 1,400,000 CU. Priority fee cost = CU price × CU consumed.
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Compute Units (CU) (compute-units) Category: Programming Model Definition: A measure of computational resources consumed by transaction execution, analogous to gas on Ethereum. Each BPF instruction costs CU; syscalls have predefined CU costs (e.g., SHA-256: 85 CU base + per-byte). Default per-instruction limit is 200,000 CU; max per-transaction is 1,400,000 CU. Priority fee cost = CU price × CU consumed. Aliases: CU Related: Compute Budget, Priority Fee
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The maximum compute units a transaction can consume. Default is 200,000 CU per instruction (max 1.4M CU per transaction). Programs can request specific limits via the ComputeBudgetProgram's SetComputeUnitLimit instruction. Under-requesting CU risks transaction failure; over-requesting wastes priority fee budget.
An optional additional fee paid on top of the base fee to increase the likelihood that a transaction is processed quickly by the current leader, expressed as a price in micro-lamports per compute unit (CU). The total priority fee equals (compute unit price × compute unit limit) / 1,000,000 lamports. Leaders sort transactions in their queue by fee-per-CU, so setting a competitive priority fee is the primary mechanism for ensuring reliable transaction landing during congestion.
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The maximum compute units a transaction can consume. Default is 200,000 CU per instruction (max 1.4M CU per transaction). Programs can request specific limits via the ComputeBudgetProgram's SetComputeUnitLimit instruction. Under-requesting CU risks transaction failure; over-requesting wastes priority fee budget.
A native Solana program (address: ComputeBudget111111111111111111111111111111) that allows transactions to configure their compute resource limits. It provides two key instructions: SetComputeUnitLimit (set the max CU a transaction can consume, up to 1.4M) and SetComputeUnitPrice (set the micro-lamport price per CU for priority fees). These instructions must appear before any program instructions in the transaction.
The price per compute unit in micro-lamports that a transaction is willing to pay as a priority fee. Set via the Compute Budget Program's SetComputeUnitPrice instruction. Higher prices increase the likelihood of a transaction being included by the leader during congestion. The effective priority fee equals the compute unit price multiplied by the compute units consumed, converted from micro-lamports to lamports.
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The maximum compute units a transaction can consume. Default is 200,000 CU per instruction (max 1.4M CU per transaction). Programs can request specific limits via the ComputeBudgetProgram's SetComputeUnitLimit instruction. Under-requesting CU risks transaction failure; over-requesting wastes priority fee budget.
An optional additional fee paid on top of the base fee to increase the likelihood that a transaction is processed quickly by the current leader, expressed as a price in micro-lamports per compute unit (CU). The total priority fee equals (compute unit price × compute unit limit) / 1,000,000 lamports. Leaders sort transactions in their queue by fee-per-CU, so setting a competitive priority fee is the primary mechanism for ensuring reliable transaction landing during congestion.
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The fundamental data storage unit on Solana. Every piece of state is stored in an account identified by a 32-byte public key. Accounts hold a lamport balance, an owner program, a data byte array (up to 10MB), and an executable flag. Only the owning program can modify an account's data, but anyone can credit lamports to it.
Executable code deployed on-chain, equivalent to a smart contract on other blockchains. Programs are stateless—they store no data themselves but read/write data in separate accounts they own. Programs are compiled to SBF bytecode and loaded via the BPF Loader. Every program has a unique Program ID (its account's public key).
A single operation within a transaction that invokes a program. An instruction specifies: (1) the program ID to call, (2) an array of account metas (pubkey, is_signer, is_writable), and (3) an opaque data byte array. Programs decode the instruction data to determine which operation to perform.
An atomic unit of execution containing one or more instructions, a recent blockhash, and one or more signatures. All instructions in a transaction execute sequentially and atomically—if any instruction fails, the entire transaction reverts. Transactions have a 1,232-byte size limit (matching IPv6 MTU) and a default 200,000 CU budget.