The process of reclaiming an account's lamports and marking it for deletion. To close an account: transfer all lamports to a recipient, zero out the data, and (in Anchor) set the discriminator to a closed sentinel. The runtime garbage-collects zero-lamport accounts. Failing to zero data enables revival attacks.
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The process of reclaiming an account's lamports and marking it for deletion. To close an account: transfer all lamports to a recipient, zero out the data, and (in Anchor) set the discriminator to a closed sentinel. The runtime garbage-collects zero-lamport accounts. Failing to zero data enables revival attacks.
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Accounts, instructions, PDAs, transactions, and execution flow.
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Close Account (close-account) Category: Programming Model Definition: The process of reclaiming an account's lamports and marking it for deletion. To close an account: transfer all lamports to a recipient, zero out the data, and (in Anchor) set the discriminator to a closed sentinel. The runtime garbage-collects zero-lamport accounts. Failing to zero data enables revival attacks. Related: Rent, Lamport, Account
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A fee mechanism that charges accounts for storing data on-chain. Accounts must maintain a minimum lamport balance proportional to their data size (~6.96 SOL per MB) to be rent-exempt. Since 2022, all new accounts must be rent-exempt at creation. Accounts falling below the threshold are removed during rent collection.
The smallest unit of SOL, named after Leslie Lamport. 1 SOL = 1,000,000,000 (10^9) lamports. All balances and transfers on Solana are denominated in lamports internally. The minimum balance for an account to be rent-exempt is calculated in lamports based on the account's data size.
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.
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A System Program instruction that creates a new account with specified space and owner, funding it with enough lamports for rent exemption. Parameters: from (fee payer), to (new account keypair), lamports, space (bytes), and owner (program ID). The new account's data is zero-initialized.
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.
The byte array stored in an account that holds program-specific state. Data is typically serialized using Borsh and must be explicitly allocated at account creation. The maximum data size is 10MB. Programs are responsible for defining and managing their own data layout, including discriminators for type identification.
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A fee mechanism that charges accounts for storing data on-chain. Accounts must maintain a minimum lamport balance proportional to their data size (~6.96 SOL per MB) to be rent-exempt. Since 2022, all new accounts must be rent-exempt at creation. Accounts falling below the threshold are removed during rent collection.
The smallest unit of SOL, named after Leslie Lamport. 1 SOL = 1,000,000,000 (10^9) lamports. All balances and transfers on Solana are denominated in lamports internally. The minimum balance for an account to be rent-exempt is calculated in lamports based on the account's data size.
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.
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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.