Smooth Termux:X11 performance

Make an official Termux:X11 desktop responsive and understand when to disable its compositor

This page covers the official termux/termux-x11 Android app and companion Termux package used to display a uDroid desktop.

Quick fix

If moving windows, opening menus, or scrolling feels slow, disable desktop compositing first.

For XFCE, open a terminal inside the running desktop and use:

xfconf-query \
  -c xfwm4 \
  -p /general/use_compositing \
  -s false

You can also open Settings → Window Manager Tweaks → Compositor and turn off Enable display compositing.

The window manager remains active. Windows can still be moved, resized, maximized, and switched. Only the extra compositing stage and effects such as shadows and transparency are disabled.

Touch-friendly XFCE launch

After starting the official Termux:X11 server, use larger GTK, Qt, and pointer scaling for XFCE on a phone-sized display:

export DISPLAY=:0
export XDG_SESSION_TYPE=x11
export GDK_BACKEND=x11
export GDK_SCALE=2
export QT_SCALE_FACTOR=2
export XCURSOR_SIZE=48

dbus-launch --exit-with-session xfce4-session

If dbus-launch is missing on Ubuntu or Debian:

apt update
apt install dbus-x11

If dbus-launch does not work in your environment, try:

dbus-run-session -- startxfce4

Use a scale of 1 instead of 2 on a tablet, external display, or whenever the interface becomes too large.

Termux:X11 also supports a server DPI option. Set it when starting the server from Termux:

termux-x11 :0 -dpi 160 &

Restart the Termux:X11 server after changing its DPI. Use either server DPI or application scaling first; combining both can make the interface too large.

Which desktop should I use?

For a uDroid desktop displayed through official Termux:X11:

Priority	Recommended desktop	Why
Responsive desktop and low overhead	XFCE without compositing	It avoids an unnecessary full-screen composition stage and is easy to scale for touch.
Most complete touch-first interface	GNOME	It has system-wide touchscreen gestures and an on-screen keyboard, but GNOME Shell requires its Mutter compositor and is substantially heavier.
Touch mode and extensive customization	KDE Plasma	Plasma can enlarge interface elements for touch, but KWin compositing is more demanding on an incomplete or copy-based X11 presentation path.

XFCE does not provide GNOME-style system gestures. Official Termux:X11 provides touchpad-emulation and simulated-touchscreen input modes, while desktop scaling makes the resulting controls easier to target with a finger.

Why disabling compositing helps

Rendering an application and displaying its window are separate operations. On a conventional Linux desktop, DRM, GBM, DMA-BUF, explicit synchronization, and a GPU compositor can make the final composition nearly zero-copy.

Termux:X11 environments do not always provide that complete path for every desktop, guest driver, and device. A composited frame can instead travel through several stages:

If DMA-BUF sharing, GPU import, or release fences are unavailable, one or more of those stages may become a CPU copy. The compositor may also redraw most of the screen for a small menu, cursor, or window movement.

With compositing disabled, the shorter route is:

This removes an off-screen redirection and full-desktop blending stage. It usually reduces:

• CPU usage and memory bandwidth

• buffer copies

• synchronization waits

• touch-to-display latency

• stutter while moving windows or opening menus

A smoother non-composited desktop does not prove that GPU acceleration is working. It may simply mean that the system is doing much less presentation work.

Trade-offs

Keep compositing disabled when responsiveness matters more than visual effects. Depending on the desktop and X11 server, you may lose:

• shadows, transparency, blur, and some animations

• live window previews and overview effects

• compositor-controlled tear prevention

You may see tearing during video playback or fast scrolling. If that happens, compare the result with compositing enabled rather than assuming either mode is universally better.

Re-enable XFCE compositing

Run this from a terminal inside the same XFCE session:

xfconf-query \
  -c xfwm4 \
  -p /general/use_compositing \
  -s true

Re-enable it when Termux:X11 performs well with your desktop, display resolution, device, and guest graphics driver. Renderer detection alone does not prove that the final composited frame is presented without an expensive copy.

Common problems

Failed to init libxfconf

Run xfconf-query from a terminal opened inside XFCE. A separately launched PRoot or ADB shell may not have the desktop session's D-Bus address and authentication context. Use the graphical Window Manager Tweaks setting if the command still fails.

Another compositing manager is running

Only one compositor can own an X11 screen. Stop the old desktop session or restart the X11 display before starting another compositor.

How to compare both modes

Use the same display resolution and applications, then:

1. Move a large window continuously for ten seconds.

2. Open and close a menu repeatedly.

3. Scroll a long page while watching touch response.

4. Compare CPU usage with top.

glxgears can confirm that frames are being produced, but it is not a reliable desktop-performance benchmark.

Further reading

• Official Termux:X11 README

• GNOME touchscreen gestures

• KDE Plasma Touch Mode