ChunkedVec

Note: This is my first Rust library, created primarily as a learning exercise. While functional, it may not be optimized for production use.

ChunkedVec is a vector-like data structure that stores elements in fixed-size chunks. It provides a Vec-like interface while offering unique advantages in memory management and growth characteristics.

Features

• Chunk-based storage with configurable chunk size (default: 64)
• Standard vector-like interface with index-based access
• Efficient memory allocation during growth
• O(1) random access time complexity

Use Cases

ChunkedVec is particularly well-suited for:

• Scenarios with frequent append operations where traditional Vec's reallocation costs are significant
• Applications requiring dynamic buffers or logging systems
• Cases where memory fragmentation is acceptable in exchange for reduced reallocation overhead

Performance Characteristics

Advantages

• Low Growth Cost: Unlike Vec which needs to reallocate and copy all elements when growing, ChunkedVec only needs to allocate a new chunk
• Efficient Random Access: O(1) access time through simple chunk index and offset calculations
• Memory Efficiency: Reduced reallocation overhead compared to Vec

Trade-offs

• Memory Layout: Elements are stored in separate chunks, which may lead to some memory fragmentation
• Access Overhead: Slightly higher access cost compared to Vec due to additional calculations and indirection
• Implementation Complexity: More complex internal structure compared to continuous storage

Usage Example

use chunked_vec::ChunkedVec;

fn main() {
    let mut vec = ChunkedVec::<i32>::new();
    vec.push(1);
    vec.push(2);
    vec.push(3);
    
    assert_eq!(vec[0], 1);
    assert_eq!(vec[1], 2);
    assert_eq!(vec[2], 3);
}