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Latency baseline: Sunshine/Moonlight (phase 0)

The target for phase 1 is glass-to-glass < 20 ms at 1080p60 on the LAN. The baseline is measured on the same scene with Sunshine (preinstalled on Bazzite) and Moonlight, before Fernsicht is measured against the same scene.

Setup
Host Bazzite, KDE Plasma (Wayland), Radeon RX 7800 XT
Client [device, OS, GPU]
Network [cable/Wi-Fi, switch, link rate]
Client monitor [model, refresh rate]
Sunshine [version], capture: KMS, encoder: VAAPI H.264
Moonlight [version], 1920×1080, 60 fps, [bitrate] Mbit/s, V-Sync off, frame pacing off

Method

  1. On the host, show a stopwatch with milliseconds in full screen (for example a web page with performance.now()); next to it, the client monitor with the stream.
  2. A phone in slow-motion mode (240 fps, that is 4.2 ms per frame) films both screens at the same time.
  3. Evaluate 20 single frames per run: the host display minus the client display. Note the median and p95.
  4. In addition, take a photo of Moonlight's statistics overlay (Ctrl+Alt+Shift+S): network latency, decode time, queue time.
  5. Repeat with 1 % artificial packet loss: sudo tc qdisc add dev <iface> root netem loss 1% (on the host), afterwards sudo tc qdisc del dev <iface> root.

Results

Run Date Median p95 Moonlight overlay (network / decode) Artifacts at 1 % loss
Sunshine 1080p60 [YYYY-MM-DD] [ms] [ms] [ms / ms] [yes/no]
Sunshine 1080p120
Fernsicht 1080p60

Fernsicht's own measurement

The client measures every stage per frame (capture, encode, network, decode, display) using timestamps in the packet header and an NTP-like clock synchronization:

# Host
fernsicht-host-agent --bind 0.0.0.0:47800
# Client, optionally with artificial packet loss
fernsicht-client <host-ip>:47800 --fps 60 --bitrate 20000 --loss 0.01 --duration 30

The overlay measures up to the hand-off to the presenter. It does not include the monitor's scan-out time, so the phone slow-motion measurement remains the acceptance test.