OGGlossary OSSolana vocabulary rebuilt for builders.
ENPT-BRES
Programming Model

Syscall (System Call)

The interface through which SBF programs request services from the Solana runtime, analogous to OS system calls. Syscalls provide access to operations that cannot be implemented in userspace BPF code: cryptographic functions (SHA-256, Keccak, Poseidon, secp256k1 recovery), logging (sol_log), account data access, CPI (invoke/invoke_signed), program return data, and sysvar reads. Each syscall has a defined compute unit cost.

IDsyscallAliasSystem Call
Plain meaning

Plain meaning

Start with the shortest useful explanation before going deeper.

The interface through which SBF programs request services from the Solana runtime, analogous to OS system calls. Syscalls provide access to operations that cannot be implemented in userspace BPF code: cryptographic functions (SHA-256, Keccak, Poseidon, secp256k1 recovery), logging (sol_log), account data access, CPI (invoke/invoke_signed), program return data, and sysvar reads. Each syscall has a defined compute unit cost.

Mental model

Mental model

Use the quick analogy first so the term is easier to reason about when you meet it in code, docs, or prompts.

Think of it as one of the core moving pieces your program reads, writes, or invokes at runtime.

Technical context

Technical context

Place the term inside its Solana layer so the definition is easier to reason about.

Accounts, instructions, PDAs, transactions, and execution flow.

Why builders care

Why builders care

Turn the term from vocabulary into something operational for product and engineering work.

This term unlocks adjacent concepts quickly, so it works best when you treat it as a junction instead of an isolated definition.

AI handoff

AI handoff

Use this compact block when you want to give an agent or assistant grounded context without dumping the entire page.

Syscall (System Call) (syscall)
Category: Programming Model
Definition: The interface through which SBF programs request services from the Solana runtime, analogous to OS system calls. Syscalls provide access to operations that cannot be implemented in userspace BPF code: cryptographic functions (SHA-256, Keccak, Poseidon, secp256k1 recovery), logging (sol_log), account data access, CPI (invoke/invoke_signed), program return data, and sysvar reads. Each syscall has a defined compute unit cost.
Aliases: System Call
Related: Solana Virtual Machine (SVM), SBF (Solana Bytecode Format), Compute Units (CU)
Glossary Copilot

Ask grounded Solana questions without leaving the glossary.

Use glossary context, relationships, mental models, and builder paths to get structured answers instead of generic chat output.

Open full Copilot workspace
Explain this code

Optional: paste Anchor, Solana, or Rust code so the Copilot can map primitives back to glossary terms.

Ask a glossary-grounded question

Ask a glossary-grounded question

The Copilot will answer using the current term, related concepts, mental models, and the surrounding glossary graph.

Concept graph

See the term as part of a network, not a dead-end definition.

These branches show which concepts this term touches directly and what sits one layer beyond them.

Branch

Solana Virtual Machine (SVM)

The Solana Virtual Machine—the execution environment that runs on-chain programs. SVM loads SBF bytecode, provides syscalls for account access and cryptographic operations, enforces compute budgets, and manages memory. The SVM is being modularized (via the SVM API) to enable use in rollups and other environments outside the main Solana validator.

SealevelBPF (Berkeley Packet Filter)
Open term
Branch

SBF (Solana Bytecode Format)

Solana Bytecode Format—Solana's customized evolution of BPF. SBF adds Solana-specific syscalls, modifies calling conventions, disables certain eBPF instructions, and adds features like position-independent code. Programs are compiled with `cargo build-sbf` and deployed as SBF ELF binaries. SBF replaced BPF as the canonical bytecode format.

Open term
Branch

Compute Units (CU)

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.

Compute BudgetPriority Fee
Open term
Next concepts to explore

Keep the learning chain moving instead of stopping at one definition.

These are the next concepts worth opening if you want this term to make more sense inside a real Solana workflow.

Core Protocol

Solana Virtual Machine (SVM)

The Solana Virtual Machine—the execution environment that runs on-chain programs. SVM loads SBF bytecode, provides syscalls for account access and cryptographic operations, enforces compute budgets, and manages memory. The SVM is being modularized (via the SVM API) to enable use in rollups and other environments outside the main Solana validator.

Open term
Core Protocol

SBF (Solana Bytecode Format)

Solana Bytecode Format—Solana's customized evolution of BPF. SBF adds Solana-specific syscalls, modifies calling conventions, disables certain eBPF instructions, and adds features like position-independent code. Programs are compiled with `cargo build-sbf` and deployed as SBF ELF binaries. SBF replaced BPF as the canonical bytecode format.

Open term
Programming Model

Compute Units (CU)

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.

Open term
Programming Model

System Program

The built-in native program (address: 11111111111111111111111111111111) responsible for creating new accounts, transferring SOL between accounts, allocating account data space, and assigning account ownership to programs. It is the only program that can create new accounts and is invoked in nearly every transaction.

Open term
Commonly confused with

Terms nearby in vocabulary, acronym, or conceptual neighborhood.

These entries are easy to mix up when you are reading quickly, prompting an LLM, or onboarding into a new layer of Solana.

Programming Modelsystem-program

System Program

The built-in native program (address: 11111111111111111111111111111111) responsible for creating new accounts, transferring SOL between accounts, allocating account data space, and assigning account ownership to programs. It is the only program that can create new accounts and is invoked in nearly every transaction.

Open term
Related terms

Follow the concepts that give this term its actual context.

Glossary entries become useful when they are connected. These links are the shortest path to adjacent ideas.

Core Protocolsvm

Solana Virtual Machine (SVM)

The Solana Virtual Machine—the execution environment that runs on-chain programs. SVM loads SBF bytecode, provides syscalls for account access and cryptographic operations, enforces compute budgets, and manages memory. The SVM is being modularized (via the SVM API) to enable use in rollups and other environments outside the main Solana validator.

Open term
Core Protocolsbf

SBF (Solana Bytecode Format)

Solana Bytecode Format—Solana's customized evolution of BPF. SBF adds Solana-specific syscalls, modifies calling conventions, disables certain eBPF instructions, and adds features like position-independent code. Programs are compiled with `cargo build-sbf` and deployed as SBF ELF binaries. SBF replaced BPF as the canonical bytecode format.

Open term
Programming Modelcompute-units

Compute Units (CU)

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.

Open term
More in category

Stay in the same layer and keep building context.

These entries live beside the current term and help the page feel like part of a larger knowledge graph instead of a dead end.

Programming Model

Account

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.

Open term
Programming Model

Program

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).

Open term
Programming Model

Instruction

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.

Open term
Programming Model

Transaction

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.

Open term