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Performance and Games

What dominates performance

Hardware acceleration decides everything. Match the guest architecture to the host so auto picks KVM (Linux), HVF (Apple Silicon) or WHPX (Windows). Cross-architecture guests fall back to TCG emulation, which is roughly an order of magnitude slower. Homebrew's qemu-system-x86_64 on macOS supports TCG only, so Intel Macs emulating an x86_64 guest get no accelerator at all.

All knobs below are in Settings, are stored per host, and default to the previous behavior:

  • CPU cores and memory: Android 13 with Waydroid wants at least 4 GiB RAM and 2 vCPUs; 6-8 GiB and 4-6 cores are comfortable. Defaults scale with the host.
  • CPU model: host passes the real CPU model through (fastest on KVM/HVF), max exposes the widest guest feature set, qemu64 is the portable x86_64 baseline. TCG and WHPX resolve to max automatically because they expose no host-passthrough model.
  • TCG threads: multi spreads guest CPU emulation over host threads and helps cross-architecture guests; single is the fallback when a multi-threaded TCG build misbehaves. Hardware accelerators ignore this setting.
  • Disk cache: writeback (default) uses the host page cache, none switches the disk to direct I/O, unsafe also drops guest flush requests. none needs O_DIRECT support and can fail on some filesystems; unsafe risks the guest filesystem when the host crashes.
  • Display quality: responsive, balanced (default) and sharp map to noVNC quality levels 3, 6 and 9. Lower levels compress frames harder, so both ends spend less time encoding and decoding and mouse, touch and swipe input feel immediate; sharp keeps text crisp at the cost of input latency. If the interface feels laggy, drop to responsive before buying more cores.
  • Disable log pane while gaming; it polls the QEMU log file on the GUI thread.

Measured results

Apple Silicon host (macOS ARM64), QEMU 11.1.1, HVF, 4 vCPUs, 4096 MiB RAM: Android 13 (LineageOS 20, arm64_only) on the Ubuntu 24.04 test guest, built-in screen 1280x800 at 74 Hz.

  • Notification shade animation, continuous swipes over 5 seconds: 331 frames, 64.9 fps (second run: 321 frames, 63.8 fps). Janky frames 1.3-3.1%, frame time p50 5 ms, p90 7-9 ms, p99 69-113 ms.
  • Host QEMU process during that animation: 1.5 cores busy, ~4.5 GiB RSS.
  • Idle Android container: under 1% guest CPU.
  • Android graphics pipeline is Skia/OpenGL inside Waydroid's software renderer; no host GPU is involved.

Games

2D, casual and turn-based games are playable on HVF/KVM/WHPX with 4 GiB and four cores: the UI itself sustains roughly 60 fps, as measured above. Demanding 3D games are not: Android renders through Waydroid's software GL, every frame is re-encoded by VNC, and neither GPU passthrough nor audio forwarding exists yet.

To make demanding games viable the backend needs guest 3D acceleration (virtio-gpu with virglrenderer, or host GPU passthrough), audio forwarding, and lower VNC latency. None of that is implemented; the safe advice is to treat smooth 3D play as out of scope today and to raise RAM/vCPU only on hosts with spare capacity.