Varena

Varena is a .NET library that provides a fast and lightweight arena allocator using virtual memory.

Features

• Create very large continuous byte buffers and arrays (e.g 1 TiB) of data without committing the virtual memory to the physical memory.
  • Only use the memory that is allocated, not the total capacity reserved!
• Fast bump allocator with a commit per block (default is 64 KiB of memory committed)
• Use VirtualBuffer for manipulating bytes.
• Use VirtualArray<T> for manipulating a dynamic array of unmanaged data.
• Compatible with .NET6.0+ and on all platforms (Windows, Linux, macOS)

Usage

using Varena;

// The manager keeps track of all created arenas (buffers, arrays)
using var manager = new VirtualArenaManager();

// Create a byte buffer and reserve 1 GiB of continuous memory (but not yet allocated)
var arena1 = manager.CreateBuffer("Arena1", 1 << 30);
// Allocate 1024 bytes -> The arena commits a block 64 KiB of memory (configurable)
var span = arena1.AllocateRange(1024);
span[0] = 1;
// Allocate 2048 bytes -> The arena keeps allocating in the previous commit block of 64 KiB
var span2 = arena1.AllocateRange(2048);
span2[0] = 1;

// Create a data array and reserve 1 MiB of continuous memory (but not yet allocated)
var arena2 = manager.CreateArray<Guid>("Arena2", 1 << 20);
// Allocate sizeof(Guid) * 1024 bytes -> The arena commits a block 64 KiB of memory (configurable)
var span3 = arena2.AllocateRange(1024);
span3[0] = Guid.NewGuid();

Documentation

You will find more details about how to use Varena in this user guide.

License

This software is released under the BSD-Clause 2 license.

Author

Alexandre Mutel aka xoofx.