test

ddtrace/tracer/tracer.go

@@ -397,6 +397,7 @@ func (t *tracer) worker(tick <-chan time.Time) {
 			t.sampleChunk(trace)
 			fmt.Printf("[DEBUG] Post-sampleChunk willSend=%v spans=%d\n", trace.willSend, len(trace.spans))
 			if len(trace.spans) != 0 {
+				fmt.Printf("[DEBUG] Actually sending trace: willSend=%v spans=%d\n", trace.willSend, len(trace.spans))
 				t.traceWriter.add(trace.spans)
 			}
 		case <-tick:
@@ -424,6 +425,7 @@ func (t *tracer) worker(tick <-chan time.Time) {
 					t.sampleChunk(trace)
 					fmt.Printf("[DEBUG] Post-sampleChunk willSend=%v spans=%d\n", trace.willSend, len(trace.spans))
 					if len(trace.spans) != 0 {
+						fmt.Printf("[DEBUG] Actually sending trace: willSend=%v spans=%d\n", trace.willSend, len(trace.spans))
 						t.traceWriter.add(trace.spans)
 					}
 				default:
@@ -445,9 +447,15 @@ type chunk struct {
 
 // sampleChunk applies single-span sampling to the provided trace.
 func (t *tracer) sampleChunk(c *chunk) {
+	fmt.Printf("[DEBUG] sampleChunk entry with willSend=%v\n", c.willSend)
 	if len(c.spans) > 0 {
-		if p, ok := c.spans[0].context.SamplingPriority(); ok && p > 0 {
-			// The trace is kept, no need to run single span sampling rules.
+		if p, ok := c.spans[0].context.SamplingPriority(); ok {
+			fmt.Printf("[DEBUG] Existing sampling priority: %d\n", p)
+			// Key change: Set willSend based on priority
+			c.willSend = p > 0
+			if !c.willSend {
+				fmt.Printf("[DEBUG] Setting willSend=false due to priority %d\n", p)
+			}
 			return
 		}
 	}
@@ -780,18 +788,14 @@ func (t *tracer) sample(span *span) {
 		span.setMetric(sampleRateMetricKey, rs.Rate())
 	}
 
-	// First try trace rules sampling
-	if t.rulesSampling.SampleTraceGlobalRate(span) {
-		fmt.Printf("[DEBUG] Global rate sampled span\n")
-		return
-	}
-	if sampled := t.rulesSampling.SampleTrace(span); sampled || t.rulesSampling.HasSpanRules() {
-		// If we have span rules or the trace was sampled, return here
-		fmt.Printf("[DEBUG] Rules sampling decision: %v\n", sampled)
+	// Check rules first
+	if sampled := t.rulesSampling.SampleTrace(span); !sampled {
+		fmt.Printf("[DEBUG] Rules sampling rejected span\n")
+		span.context.trace.drop()
+		span.context.trace.setSamplingPriority(ext.PriorityAutoReject, samplernames.RuleRate)
 		return
 	}
 
-	// Only fall back to priority sampling if no rules matched
 	fmt.Printf("[DEBUG] Priority sampling span\n")
 	t.prioritySampling.apply(span)
 }