xalloc

Dynamic suballocators for external memory (e.g., Vulkan device memory).

Provided Algorithms

Generic

Name	Time Complexity	Space Complexity
TLSF (Two-Level Segregated Fit)	O(1)	O(N + log size)
Free space bitmap	O(size)	O(size)

Specialized

Name	Time Complexity	Space Complexity
Ring buffer	O(1)	O(N)

(size: heap size measured by the number of allocation units, N: number of allocations)

Examples

use xalloc::{SysTlsf, SysTlsfRegion};
let mut tlsf = xalloc::SysTlsf::new(8u32);

// Allocate regions
let alloc1: (SysTlsfRegion, u32) = tlsf.alloc(4).unwrap();
let alloc2: (SysTlsfRegion, u32) = tlsf.alloc(4).unwrap();
let (region1, offset1) = alloc1;
let (region2, offset2) = alloc2;
println!("allocated #1: {:?}", (&region1, offset1));
println!("allocated #2: {:?}", (&region2, offset2));

// Deallocate a region
tlsf.dealloc(region1).unwrap();

// Now we can allocate again
tlsf.alloc(2).unwrap();
tlsf.alloc(2).unwrap();

Feature Flags

• nightly — Enables optimizations which currently require a Nightly Rust compiler. This flag is now unused due to the stabilization of NonNull in Rust 1.25.

License: MIT