24x7 RTMP desktop stream, client side + UAT PASS (#798)

Whole-screen KDE capture -> x264 -> RTMP, fenced to the rt slice.
Loopback mediamtx receiver; Cloudron cutover = one creds edit.
Detail: https://projects.knownelement.com/issues/798#note-4519

💘 Generated with Crush

Assisted-by: Crush:glm-5.2

TRACKING.md

@@ -22,10 +22,12 @@ One table, updated in place at each checkpoint. States: done ✅ / doing 🔄 /
 | #616 | macos | ⏳ | macOS VM on pfv-tsys5 (headless CI + iOS dev) — blocked by #601 |
 | #631 | hidpi | ✅ | 150% scaling both accounts (Xft.dpi 144 + kdeglobals, persisted); cursor box RESOLVED 2026-09-05 (human verdict: gone): core shadowless cursors + xrdp new_cursors=false (server-side draw; Jump drops cursor alpha). Follow-on = #679 |
 | #679 | rdp-perf | ⏳ | 16K compressed-bitmap drops at 5160 (lag/stale updates); 1MB send buffer STAGED (applies at next reconnect); EGFX-at-24bpp retest queued (human-timed) |
+| #798 | rtmp | 🔄 | 24x7 desktop stream CLIENT SIDE DONE + UAT PASS 2026-09-05 (h264+aac 1920w ~30fps, 187% of the 2-core rt-slice fence, self-heal proven; logs/19-rtmp-uat.out). Loopback receiver ukrrs-ultix-rtmp-rx UP. HUMAN OWES: run ./18-rtmp-stream.sh (installs service), later paste Cloudron RTMP URL into ~/.creds/rtmp-stream.env + restart. See STREAMING.md |
 
 Inbox (mid-task interrupts): none.
 
 Decisions log (latest wins):
+- 2026-09-05 (morning, #798): 24x7 RTMP desktop stream built client-side. Host ffmpeg 7.1.5 ruled OK to use host-side (human: "it's fine... special case working on host", same family as the #610 open-terminal exception; nothing new installed). Architecture: systemd ukrrs-rtmp-stream.service (User=reachableceo, Slice=ukrrs-rt.slice = cores 6-7, MemoryMax 4G) -> /usr/local/sbin/ukrrs-rtmp-stream.sh: discovers the NEWEST xorgxrdp display of UID 1001 via /proc scan (xrdp display numbers move; after reboot no session exists until first RDP login - stream waits), x11grab whole screen + pulse monitor, x264 -> FLV/RTMP. TUNING MEASURED: 2560w veryfast does NOT fit the 2-core fence (saturates at ~13fps); 1920w superfast runs 187% of one core with headroom - interim operating point until #601. x11grab on xorgxrdp tops at ~20 delivered fps (GetImage latency, not CPU). Secrets: RTMP_URL only in ~/.creds/rtmp-stream.env. Local loopback receiver: mediamtx 1.20.1 pinned, 127.0.0.1:1935 only, compose rtmp/. mediamtx v1.20 key lesson: booleans are rtsp/hls/webrtc/srt/moq/api/metrics/pprof/playback (no *Disable keys, no rtmpTransports). Cloudron streaming server = final target, details pending from human; cutover = edit creds + restart (STREAMING.md).
 - 2026-09-05 (early AM, post-update-reboot outage, #611): two independent RDP killers after the 6.12.105/u2 reboot: (1) xrdp 0.10.1 waitforx races xorgxrdp deferred-RandR output creation and goes blind for its whole 30s window ("Timed out waiting for RandR outputs" -> session killed -> Jump error + black screen); the u2 security NMU ALSO intermittently execs waitforx with EMPTY argv (observed 03:58:38) which the real binary rejects. Fix = wrapper at /usr/lib/x86_64-linux-gnu/xrdp/waitforx: defaults -d from $DISPLAY when argv empty + forces an xrandr RandR query past the deferred window, then execs pristine waitforx.real; invocations logged to /var/log/xrdp-fix/. (2) /etc/X11/Xsession.d/90xbrlapi runs /bin/xbrlapi in the FOREGROUND; brltty inactive (no BrlAPI socket) -> hangs forever -> Xsession never reaches startplasma-x11 -> connected-but-black screen. Hook disabled (renamed .disabled; no braille HW on this VM). Plus new_cursors=false in xrdp.ini (cursor black box: server-side cursor draw, pairs with #631 core cursor theme). All re-appliable: 17-fix-rdp-postupdate.sh (idempotent, session-safe, self-elevating). LESSON: bouncing the xrdp FRONT-END while a session lives orphans sesman state -> next login CREATES a second session instead of reconnecting -> two KDE sessions on one user bus fight (half-drawn desktop); recovery = kill all session procs + verify no plasma left (user@1001 stop can hang when crush lives inside it). Diagnostic gold: shim the helper binary (waitforx) to dump argv+env at the failure point.
 - 2026-09-01 (midday): RDP #611 diagnosis: xrdp 0.10.1/xorgxrdp 0.10.2 serves 5160x2160 CLEANLY on every codec (EGFX-RFXPro, NSCodec, bitmaps) and mid-session resize 2816->5160 (freerdp headless UAT, Xvfb screenshots; ASCII-render analysis). Jump-client corruption pinned to EGFX large-frame path -> XRDP_GFX_MAX_COMPRESSED_BYTES=32MB + FRAMES_IN_FLIGHT=2 via xrdp.service.d drop-in (12-fix-rdp-bigres.sh, idempotent, restart-guards on active sessions). Scratch user rdptest = the UAT account (remove after #611 closes). Sudoers: reachableceo -> offstage NOPASSWD (narrow, /etc/sudoers.d/reachableceo-to-offstage). Harness note: crush v0.91.2 hardcodes a bash command blocklist, no config override (upstream #2761); leading-word prefix bypasses it.
 - 2026-09-01 (afternoon): #615 microvm LIVE: qemu -M microvm + KVM engine (apt-only deps), firecracker v1.16.1 installed but its KVM cap check (0x38 = USER_MEMORY/SET_TSS_ADDR/VAPIC) refuses this nested Westmere KVM — retry MICROVM_ENGINE=firecracker post-#601. Per-user tap pools mv-r0..3/mv-o0..3 (/30s in 172.30.0/1.x) + iptables NAT via microvm-net.service; kvm group added both accounts (one re-login activates). UAT: boot->ssh 27.9s first boot (cloud-init+growpart 3->9.7G), apt OK through NAT, graceful stop 6.4s. #616 macOS VM ticket created w/ blocks-relation on #601. REBUILD.md + docs/state capture (14-capture-state.sh) landed; README/NEXT/REPORT/RUNBOOK synced (stale multiqueue text). mred = the Redmine CLI for all ticket work (~/.local/bin/mred).