octobuild

Overview

This project allows you to speedup re-compilation of Unreal Engine (and UE-based games) by caching intermediate compilation files, reducing time by 60-90%.

Supported platforms

• Linux

• macOS

• PS4

• PS5

• Win64

• Xbox One

• Xbox Series

Installation

Chocolatey (Windows)

octobuild is available via Chocolatey package manager. If you already have Chocolatey installed, you can just run the following command from elevated console:

choco install octobuild

WinGet (Windows)

winget install octobuild

Manual (Windows)

1. Download MSI installer

2. Double-click on it

3. Next-next-next

deb package (Ubuntu/Debian)

You can install octobuild on Ubuntu/Debian using the following commands:

# Set up repository
curl -1sLf 'https://dl.cloudsmith.io/public/octobuild/octobuild/setup.deb.sh' | sudo -E bash

# Install octobuild
sudo apt-get install octobuild

Manual (Ubuntu/Debian)

1. Download deb package

2. Install it via dpkg -i <octobuild>.deb

Homebrew (macOS/Linux)

octobuild is available via Homebrew package manager.

If you already have Homebrew configured, you can install octobuild with a single command:

brew install octobuild

Usage

You do not need to use octobuild directly. Just build Unreal Engine as usual, via Unreal Build Tool, Unreal Automation Tool or your IDE. Under the hood, they will automatically use octobuild.

Also see Linux notes.

Configuration files

You can list configuration files and check actual configuration by running ib_console/xgConsole without parameters.

Platform	System-wide config	User-specific config (overrides system defaults)
Linux	/etc/octobuild/octobuild.conf	$XDG_CONFIG_HOME/octobuild/octobuild.conf (with fallback to ~/.config/octobuild/octobuild.conf when $XDG_CONFIG_HOME is not set)
Windows	%ProgramData\octobuild\octobuild.conf	%AppData%\octobuild\octobuild.conf
macOS	/etc/octobuild/octobuild.conf	~/Library/Application Support/octobuild/octobuild.conf

Environment variables

Environment variables have higher priority than config files.

OCTOBUILD_CACHE (string)

specifies path to directory where octobuild cache is stored. Default is %LocalAppData%/octobuild/cache on Windows, ~/.cache/octobuild on Linux and ~/Library/Caches/octobuild on macOS.

OCTOBUILD_CACHE_LIMIT_MB (number)

specifies octobuild disk cache size limit in megabytes. Defaults is 64GB.

OCTOBUILD_PROCESS_LIMIT (number)

specifies max number of concurrent processes octobuild will spawn. Default is number of cores.

OCTOBUILD_USE_RESPONSE_FILES (bool)

specifies whether octobuild should use compiler response files to overcome commandline length limitation. Default is true on Windows and false on other platforms. Enable this if you’re getting ERROR: The filename or extension is too long. (os error 206) on Windows.

Benchmark

Linux build tested on AMD Ryzen 7 3700X, 32GB DDR4 @ 3200MHz, SSD and Unreal Engine 5.0.3 by running <engine>/Engine/Build/BatchFiles/RunUAT.sh <game>.uproject <game>Editor DebugGame Linux.

Windows build tested on Intel Core i7-9700F, 32GB DDR4 @ 2400MHz, SSD and Unreal Engine 5.0.3 by running <engine>/Engine/Build/BatchFiles/RunUBT.bat <game>.uproject <game>Editor DebugGame Win64.

Console builds tested on Intel Core i7-9700F, 32GB DDR4 @ 2400MHz, SSD and Unreal Engine 5.0.3 by running <engine>/Engine/Build/BatchFiles/RunUBT.bat <game>.uproject <game> DebugGame <platform>.

Platform	Without octobuild	octobuild (0% cache)	octobuild (100% cache)
Linux	3m54s	3m53s	36s
Win64 (MSVC 2019)	8m4s	10m6s	2m15s
PS4	6m12s	7m10s	2m34s
PS5	5m48s	6m56s	2m11s
XB1	4m40s	6m10s	1m39s
XSX	4m49s	5m42s	1m40s

Linux notes

This project requires several patches to Unreal Engine:

• #9903: Restore ability to use XGE executor on non-Windows platforms (already included in UE >= 5.2)

• #9932: Fix action graph copy action on non-Windows platforms (already included in UE >= 5.2)

• #9933: Reenable XGE on Linux

Building from source

1. Install Rust

2. (Windows only) Install Visual Studio 2019 or 2022. Enable "Desktop development with C++" workload. Also, enable "C++ 2019 Redistributable MSMs" "C++ 2022 Redistributable MSMs" in individual components.

3. Clone octobuild Git repository

4. Run cargo build in repository root to compile octobuild