# GameMode
**GameMode** is a daemon/lib combo for Linux that allows games to request a set of optimisations be temporarily applied to the host OS and/or a game process.

GameMode was designed primarily as a stop-gap solution to problems with the Intel and AMD CPU powersave or ondemand governors, but is now host to a range of optimisation features and configurations.

Currently GameMode includes support for optimisations including:
* CPU governor
* I/O priority
* Process niceness
* Kernel scheduler (`SCHED_ISO`)
* Screensaver inhibiting
* GPU performance mode (NVIDIA and AMD), GPU overclocking (NVIDIA)
* Custom scripts

GameMode packages are available for Ubuntu, Debian, Solus, the AUR, Gentoo, Fedora, OpenSUSE and possibly more.

Issues with GameMode should be reported here in the issues section, and not reported to Feral directly.

---
## Requesting GameMode

For games which integrate GameMode support (see list later on), simply running the game will automatically activate GameMode.

For others, you must manually request GameMode when running the game. This can be done by launching the game through `gamemoderun`:
```bash
gamemoderun ./game
```
Or edit the Steam launch options:
```bash
gamemoderun %command%
```

Note: for older versions of GameMode (before 1.3) use this string in place of `gamemoderun`:
```
LD_PRELOAD="$LD_PRELOAD:/usr/\$LIB/libgamemodeauto.so.0"
```
**Please note the backslash here in `\$LIB` is required.**

---
## Configuration

The daemon is configured with a `gamemode.ini` file. [example/gamemode.ini](https://github.com/FeralInteractive/gamemode/blob/master/example/gamemode.ini) is an example of what this file would look like, with explanations for all the variables.

Config files are loaded and merged from the following directories, in order:
1. `/usr/share/gamemode/`
2. `/etc/`
3. `$XDG_CONFIG_HOME` or `$HOME/.config/`
4. `$PWD`

---
## Note for Hybrid GPU users

It's not possible to integrate commands like optirun automatically inside GameMode, since the GameMode request is made once the game has already started. However it is possible to use a hybrid GPU wrapper like optirun by starting the game with `gamemoderun`.

You can do this by setting the environment variable `GAMEMODERUNEXEC` to your wrapper's launch command, so for example `GAMEMODERUNEXEC=optirun` or `GAMEMODERUNEXEC="env DRI_PRIME=1"`. This environment variable can be set globally, so that the same prefix command does not have to be duplicated everywhere you want to use `gamemoderun`.

GameMode will not be injected to the wrapper.

---
## Apps with GameMode integration

### Games
The following games are known to integrate GameMode support (meaning they don't require any additional configuration to activate GameMode while running):
* DiRT 4
* Rise of the Tomb Raider
* Total War: Three Kingdoms
* Total War: WARHAMMER II
* Total War Saga: Thrones of Britannia

### Others
Other apps which can integrate with GameMode include:
* GNOME Shell ([via extension](https://github.com/gicmo/gamemode-extension)) - indicates when GameMode is active in the top panel.

---
## Development [![Build Status](https://travis-ci.org/FeralInteractive/gamemode.svg?branch=master)](https://travis-ci.org/FeralInteractive/gamemode)

The design of GameMode has a clear-cut abstraction between the host daemon and library (`gamemoded` and `libgamemode`), and the client loaders (`libgamemodeauto` and `gamemode_client.h`) that allows for safe use without worrying about whether the daemon is installed or running. This design also means that while the host library currently relies on `systemd` for exchanging messages with the daemon, it's entirely possible to implement other internals that still work with the same clients.

See repository subdirectories for information on each component.

### Install Dependencies
GameMode depends on `meson` for building and `systemd` for internal communication. This repo contains a `bootstrap.sh` script to allow for quick install to the user bus, but check `meson_options.txt` for custom settings.

#### Ubuntu/Debian (you may also need `dbus-user-session`)
```bash
apt install meson libsystemd-dev pkg-config ninja-build git libdbus-1-dev
```
#### Arch
```bash
pacman -S meson systemd git dbus
```
#### Fedora
```bash
dnf install meson systemd-devel pkg-config git dbus-devel
```
#### Gentoo
Gentoo has an ebuild which builds a stable release from sources. It will also pull in all the dependencies so you can work on the source code.
```bash
emerge --ask games-util/gamemode
```
You can also install using the latest sources from git:
```bash
ACCEPT_KEYWORDS="**" emerge --ask ~games-util/gamemode-9999
```

### Build and Install GameMode
Then clone, build and install a release version of GameMode at 1.4:

```bash
git clone https://github.com/FeralInteractive/gamemode.git
cd gamemode
git checkout 1.4 # omit to build the master branch
./bootstrap.sh
```

To uninstall:
```bash
systemctl --user stop gamemoded.service
cd build/
ninja uninstall
```

### Pull Requests
Pull requests must match with the coding style found in the `.clang-format` file, please run this before committing:
```
clang-format -i $(find . -name '*.[ch]' -not -path "*subprojects/*")
```

### Maintained by
Feral Interactive

See the [contributors](https://github.com/FeralInteractive/gamemode/graphs/contributors) section for an extended list of contributors.

---
## License

Copyright © 2017-2019 Feral Interactive

GameMode is available under the terms of the BSD 3-Clause License (Revised)

The "inih" library is distributed under the New BSD license