v1.0.0

Release Notes: v1.0.0

malloc v1.0.0 marks the first stable release version. The package now supports concurrent access, dynamic memory growth, and memory-mapped allocation.

Breaking Changes

Function signatures changed:

// Old (v0.10.0)
func NewArena(size uint64) *Arena
func NewArenaAt[T any](buf []T) *Arena

// New (v1.0.0)
func NewArena(size uint64, opts ...Opt) *Arena
func NewArenaAt[T any](buf []T, opts ...Opt) *Arena

Existing code continues to work without changes. The new optional parameters add configuration without breaking compatibility.

New Features

Thread-Safe Arenas

Arenas now protect concurrent access with a mutex. Multiple goroutines can allocate and free memory simultaneously.

arena := malloc.NewArena(64 * 1024)

// Safe to call from multiple goroutines
go func() {
    p, _ := malloc.Malloc[int](arena)
    malloc.Free(arena, p)
}()

Dynamic Growth

Arenas grow automatically when they run out of space. The backend determines how growth occurs.

// Starts small, grows as needed
arena := malloc.NewArena(1024, malloc.Backend(malloc.SliceBackend))

Memory-Mapped Allocation

The MmapBackend allocates memory through mmap(2) on Unix or VirtualAlloc on Windows. This keeps allocated memory outside the Go heap.

// Allocate 4KB via mmap
arena := malloc.NewArena(4096, malloc.Backend(malloc.MmapBackend(0, 0)))

Platforms: Linux, macOS, Windows

Improvements

• Improved error detection for double-free bugs
• Added GitHub Actions CI across Go 1.25, 1.26 and all supported platforms

Known Limitations

• The mmap backend does not support BSD systems (except Darwin)
• Growth performance depends on the backend implementation
• Minimum allocation size remains 16 bytes

Migration Guide

From v0.10.0

No code changes required. The API remains compatible.

To opt into new features:

// Enable growth
arena := malloc.NewArena(1024, malloc.Backend(malloc.SliceBackend))

// Use mmap
arena := malloc.NewArena(4096, malloc.Backend(malloc.MmapBackend(0, 0)))

Requirements

• Go 1.25 or later
• For mmap support: Linux, macOS, or Windows