Monitor: show GPU temperature and fan speed

Extends the existing per-tick nvidia-smi query with temperature.gpu and
fan.speed (no extra call); N/A values (cards without fan telemetry) are
simply omitted from the GPU line.

cmd/gpu-turnstile/main.go

@@ -847,14 +847,17 @@ type gpuWatch struct {
 	enabled bool
 	usedMB  int
 	total   int
+	tempC   int
+	fanPct  int
 	known   bool
 	foreign string // last Check result: external holders, "" when none
 	at      time.Time
 }
 
-func (g *gpuWatch) setVRAM(used, total int) {
+func (g *gpuWatch) setVRAM(st game.GPUStats) {
 	g.mu.Lock()
-	g.usedMB, g.total, g.known = used, total, true
+	g.usedMB, g.total = st.UsedMB, st.TotalMB
+	g.tempC, g.fanPct, g.known = st.TempC, st.FanPct, true
 	g.mu.Unlock()
 }
 
@@ -864,14 +867,15 @@ func (g *gpuWatch) setCheck(foreign string) {
 	g.mu.Unlock()
 }
 
-func (g *gpuWatch) get() (used, total int, known bool, foreign string, ageS int64) {
+func (g *gpuWatch) get() (st game.GPUStats, known bool, foreign string, ageS int64) {
 	g.mu.Lock()
 	defer g.mu.Unlock()
 	ageS = -1
 	if !g.at.IsZero() {
 		ageS = int64(time.Since(g.at).Seconds())
 	}
-	return g.usedMB, g.total, g.known, g.foreign, ageS
+	return game.GPUStats{UsedMB: g.usedMB, TotalMB: g.total, TempC: g.tempC, FanPct: g.fanPct},
+		g.known, g.foreign, ageS
 }
 
 // gameLoop polls for foreign GPU holders (a game, another ML job). While one
@@ -894,8 +898,8 @@ func gameLoop(ctx context.Context, cfg config.Config, log *slog.Logger, det *gam
 			log.Warn("game detection failed", "err", err)
 		}
 		gw.setCheck(summarizeHolders(holders))
-		if used, total, verr := game.QueryVRAMMB(ctx); verr == nil {
-			gw.setVRAM(used, total)
+		if st, verr := game.QueryGPUStats(ctx); verr == nil {
+			gw.setVRAM(st)
 		}
 		switch {
 		case len(holders) > 0 && !held:
@@ -1148,7 +1152,11 @@ type statusGPU struct {
 	Enabled bool `json:"enabled"`
 	UsedMB  int  `json:"used_mb"`
 	TotalMB int  `json:"total_mb"`
-	Known   bool `json:"known"`
+	// TempC/FanPct are -1 when unknown (never sampled or nvidia-smi
+	// reported N/A).
+	TempC  int  `json:"temp_c"`
+	FanPct int  `json:"fan_pct"`
+	Known  bool `json:"known"`
 	// Foreign is the last detector finding (external GPU holders), empty
 	// when the last check found none.
 	Foreign string `json:"foreign,omitempty"`
@@ -1202,12 +1210,16 @@ func statusProvider(cfg config.Config, lk *lock.Lock, comfySup *supervise.Proces
 			Version: version,
 			UptimeS: int64(time.Since(started).Seconds()),
 		}
-		used, total, known, foreign, ageS := gw.get()
+		st, known, foreign, ageS := gw.get()
 		snap.GPU = statusGPU{
 			Enabled: gw.enabled,
-			UsedMB:  used, TotalMB: total, Known: known,
+			UsedMB:  st.UsedMB, TotalMB: st.TotalMB, Known: known,
+			TempC: -1, FanPct: -1,
 			Foreign: foreign, AgeS: ageS,
 		}
+		if known {
+			snap.GPU.TempC, snap.GPU.FanPct = st.TempC, st.FanPct
+		}
 		if cfg.OllamaURL != "" {
 			d := statusDownstream{
 				Name: "ollama", URL: cfg.OllamaURL, Up: health.get("ollama"),
@@ -1232,15 +1244,15 @@ func statusProvider(cfg config.Config, lk *lock.Lock, comfySup *supervise.Proces
 			}
 			snap.Downstreams = append(snap.Downstreams, d)
 		}
-		st := lk.Status()
+		lst := lk.Status()
 		snap.Lock = statusLock{
-			State:       string(st.State),
-			Detail:      st.Detail,
-			LLMInflight: st.LLMInflight,
-			LLMWaiting:  st.LLMWaiting,
-			ImageQueue:  st.ImageQueue,
-			External:    st.External,
-			SinceS:      int64(time.Since(st.Since).Seconds()),
+			State:       string(lst.State),
+			Detail:      lst.Detail,
+			LLMInflight: lst.LLMInflight,
+			LLMWaiting:  lst.LLMWaiting,
+			ImageQueue:  lst.ImageQueue,
+			External:    lst.External,
+			SinceS:      int64(time.Since(lst.Since).Seconds()),
 		}
 		b, err := json.Marshal(snap)
 		if err != nil {

cmd/gpu-turnstile/monitor.go

@@ -225,6 +225,12 @@ func renderGPU(g statusGPU) string {
 	s := " GPU: "
 	if g.Known {
 		s += renderVRAM(g.UsedMB, g.TotalMB)
+		if g.TempC >= 0 {
+			s += fmt.Sprintf(" · %d°C", g.TempC)
+		}
+		if g.FanPct >= 0 {
+			s += fmt.Sprintf(" · fan %d%%", g.FanPct)
+		}
 	} else {
 		s += cDim + "VRAM unknown (nvidia-smi not answering)" + cReset
 	}

cmd/gpu-turnstile/monitor_test.go

@@ -32,9 +32,9 @@ func TestRenderMonitor(t *testing.T) {
 		}
 	}
 
-	snap.GPU = statusGPU{Enabled: true, Known: true, UsedMB: 4300, TotalMB: 16384, Foreign: "cyberpunk2077.exe (pid 1234)", AgeS: 12}
+	snap.GPU = statusGPU{Enabled: true, Known: true, UsedMB: 4300, TotalMB: 16384, TempC: 55, FanPct: 42, Foreign: "cyberpunk2077.exe (pid 1234)", AgeS: 12}
 	frame = renderMonitor(snap, 80)
-	for _, want := range []string{"GPU:", "4.2 GiB / 16.0 GiB used", "external:", "checked 12s ago"} {
+	for _, want := range []string{"GPU:", "4.2 GiB / 16.0 GiB used", "55°C", "fan 42%", "external:", "checked 12s ago"} {
 		if !strings.Contains(frame, want) {
 			t.Errorf("frame missing %q:\n%s", want, frame)
 		}