A sysvar (address: SysvarC1ock11111111111111111111111111111111) that provides the current slot, epoch, unix_timestamp, and leader_schedule_epoch. Programs use Clock to implement time-based logic like lockups or vesting schedules. In Anchor, accessed via `Clock::get()` or as a sysvar account in the accounts struct.
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A sysvar (address: SysvarC1ock11111111111111111111111111111111) that provides the current slot, epoch, unix_timestamp, and leader_schedule_epoch. Programs use Clock to implement time-based logic like lockups or vesting schedules. In Anchor, accessed via `Clock::get()` or as a sysvar account in the accounts struct.
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Clock Sysvar (clock) Category: Programming Model Definition: A sysvar (address: SysvarC1ock11111111111111111111111111111111) that provides the current slot, epoch, unix_timestamp, and leader_schedule_epoch. Programs use Clock to implement time-based logic like lockups or vesting schedules. In Anchor, accessed via `Clock::get()` or as a sysvar account in the accounts struct. Related: Sysvar, Slot, Epoch
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Special read-only accounts maintained by the runtime that expose cluster state to programs. Key sysvars include Clock (slot, timestamp), Rent (lamports-per-byte), EpochSchedule (epoch parameters), RecentBlockhashes, StakeHistory, and Fees. Programs access sysvars by including the sysvar account in the instruction or via the sol_get_sysvar syscall.
A time window during which a designated leader validator can produce a block. Each slot lasts approximately 400 milliseconds. Slots are numbered sequentially from genesis and grouped into epochs of 432,000 slots (~2-3 days). Not every slot produces a block—a skipped slot means the leader was offline or too slow.
A period of 432,000 slots (approximately 2-3 days) that defines a staking cycle. At each epoch boundary, the leader schedule is recalculated based on stake weights, stake activations/deactivations take effect, and inflation rewards are distributed to validators and delegators.
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Special read-only accounts maintained by the runtime that expose cluster state to programs. Key sysvars include Clock (slot, timestamp), Rent (lamports-per-byte), EpochSchedule (epoch parameters), RecentBlockhashes, StakeHistory, and Fees. Programs access sysvars by including the sysvar account in the instruction or via the sol_get_sysvar syscall.
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Special read-only accounts maintained by the runtime that expose cluster state to programs. Key sysvars include Clock (slot, timestamp), Rent (lamports-per-byte), EpochSchedule (epoch parameters), RecentBlockhashes, StakeHistory, and Fees. Programs access sysvars by including the sysvar account in the instruction or via the sol_get_sysvar syscall.
A time window during which a designated leader validator can produce a block. Each slot lasts approximately 400 milliseconds. Slots are numbered sequentially from genesis and grouped into epochs of 432,000 slots (~2-3 days). Not every slot produces a block—a skipped slot means the leader was offline or too slow.
A period of 432,000 slots (approximately 2-3 days) that defines a staking cycle. At each epoch boundary, the leader schedule is recalculated based on stake weights, stake activations/deactivations take effect, and inflation rewards are distributed to validators and delegators.
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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.