0.3.6

cmd/ts3monolith/main.go

@@ -66,14 +66,24 @@ func collect(ctx context.Context, cfg config.Config, tq *ts3.Query, rm *rrd.Mana
 		// more than it reads as useful information -- so, deliberately,
 		// a true "server went empty for a while" no longer shows as 0 in
 		// the graph, same trade-off the original app made.
+		raw := n
 		if n == 0 {
 			c2, cancel2 := context.WithTimeout(ctx, 2*time.Second)
 			last, lastErr := rm.Last(c2)
 			cancel2()
-			if lastErr == nil {
+			if lastErr != nil {
+				log.Printf("collect: raw=0, rrd lastupdate failed (writing raw 0): %v", lastErr)
+			} else {
 				n = last
 			}
 		}
+		// DEBUG=1 turns on a log line for every single collection cycle
+		// (raw TS3 reading vs. what actually got written to the RRD) --
+		// useful while diagnosing the stats collector, far too noisy to
+		// leave on permanently (one line per STATS_INTERVAL, forever).
+		if cfg.Debug {
+			log.Printf("collect: raw=%d written=%d", raw, n)
+		}
 		c3, cancel3 := context.WithTimeout(ctx, 5*time.Second)
 		defer cancel3()
 		if err := rm.Update(c3, n); err != nil {