Technique where files are mapped directly into process virtual memory, allowing the OS to handle reads/writes through page faults. Solana's AccountsDB uses memory-mapped files (AppendVec) to store account data, enabling efficient random access to gigabytes of account state without loading everything into heap memory.
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Technique where files are mapped directly into process virtual memory, allowing the OS to handle reads/writes through page faults. Solana's AccountsDB uses memory-mapped files (AppendVec) to store account data, enabling efficient random access to gigabytes of account state without loading everything into heap memory.
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Memory-Mapped I/O (memory-mapped-io) Category: Programming Fundamentals Definition: Technique where files are mapped directly into process virtual memory, allowing the OS to handle reads/writes through page faults. Solana's AccountsDB uses memory-mapped files (AppendVec) to store account data, enabling efficient random access to gigabytes of account state without loading everything into heap memory. Aliases: mmap Related: AccountsDB, AppendVec, Heap Memory
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The persistent storage layer for all Solana accounts. AccountsDB stores account data in memory-mapped AppendVec files, indexed by pubkey and slot. It supports fast lookups, handles account deduplication across slots, and periodically cleans up dead accounts. AccountsDB is the largest consumer of validator disk space.
A memory-mapped, append-only file used by AccountsDB to store account data. Each AppendVec corresponds to a specific slot and contains serialized account entries (pubkey, lamports, data, owner, etc.). AppendVecs are immutable once the slot is rooted, enabling efficient snapshotting and cleanup.
The dynamic memory region available to SBF programs during execution, defaulting to 32KB. Programs use heap memory for dynamic allocations (Vec, String, Box). The heap size can be increased up to 256KB by requesting additional compute units via the Compute Budget Program's RequestHeapFrame instruction. Heap exhaustion causes the program to fail with an AccessViolation error. Efficient programs minimize heap usage through zero-copy patterns and stack-allocated buffers.
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The persistent storage layer for all Solana accounts. AccountsDB stores account data in memory-mapped AppendVec files, indexed by pubkey and slot. It supports fast lookups, handles account deduplication across slots, and periodically cleans up dead accounts. AccountsDB is the largest consumer of validator disk space.
A memory-mapped, append-only file used by AccountsDB to store account data. Each AppendVec corresponds to a specific slot and contains serialized account entries (pubkey, lamports, data, owner, etc.). AppendVecs are immutable once the slot is rooted, enabling efficient snapshotting and cleanup.
The dynamic memory region available to SBF programs during execution, defaulting to 32KB. Programs use heap memory for dynamic allocations (Vec, String, Box). The heap size can be increased up to 256KB by requesting additional compute units via the Compute Budget Program's RequestHeapFrame instruction. Heap exhaustion causes the program to fail with an AccessViolation error. Efficient programs minimize heap usage through zero-copy patterns and stack-allocated buffers.
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A systems programming language emphasizing memory safety, zero-cost abstractions, and concurrency without a garbage collector. Rust uses an ownership model with borrow checking at compile time to prevent data races and null pointer bugs. It is the primary language for Solana program development (via Anchor or native solana-program crate) and the Agave validator client.
A statically typed superset of JavaScript that compiles to plain JavaScript. TypeScript adds type annotations, interfaces, generics, and enums to catch errors at compile time. It is the standard language for Solana client-side developmentâwallet adapters, dApp frontends, test suites, and SDK interactions (web3.js, Anchor client) are typically written in TypeScript.
The ubiquitous scripting language for web development, running in browsers and Node.js. JavaScript is dynamically typed and event-driven. Most Solana dApp frontends and scripts use JavaScript/TypeScript with libraries like @solana/web3.js. Node.js enables server-side JS for backend services, indexers, and bot development.
A JavaScript runtime built on Chrome's V8 engine that enables server-side JavaScript execution. Node.js uses an event-driven, non-blocking I/O model. In the Solana ecosystem, Node.js is used for: running Anchor tests (Mocha/Jest), backend services, transaction bots, indexers, and CLI tools. npm/yarn/pnpm manage JavaScript package dependencies.