debug: add log for debug discovery

Author: YangruiEmma

pkg/loadbalance/weighted_balancer.go

@@ -64,7 +64,7 @@ func (wb *weightedBalancer) GetPicker(ctx context.Context, e discovery.Result) P
 	picker, ok := wb.pickerCache.Load(e.CacheKey)
 	if !ok {
 		picker, _, _ = wb.sfg.Do(e.CacheKey, func() (interface{}, error) {
-			klog.CtxErrorf(ctx, "KITEX-DEBUG: start createPicker, CacheKey=%s", e.CacheKey)
+			klog.CtxErrorf(ctx, "KITEX-DEBUG: start createPicker, CacheKey=%s, instanceSize=%d", e.CacheKey, len(e.Instances))
 			p := wb.createPicker(ctx, e)
 			klog.CtxErrorf(ctx, "KITEX-DEBUG: end createPicker, CacheKey=%s", e.CacheKey)
 			wb.pickerCache.Store(e.CacheKey, p)
@@ -79,6 +79,7 @@ func (wb *weightedBalancer) createPicker(ctx context.Context, e discovery.Result
 	weightSum := 0
 	balance := true
 	cnt := 0
+	klog.CtxErrorf(ctx, "KITEX-DEBUG: createPicker, begin iterator")
 	for idx, instance := range e.Instances {
 		weight := instance.Weight()
 		if weight <= 0 {
@@ -92,6 +93,7 @@ func (wb *weightedBalancer) createPicker(ctx context.Context, e discovery.Result
 		}
 		cnt++
 	}
+	klog.CtxErrorf(ctx, "KITEX-DEBUG: createPicker, end iterator, size=%d", len(instances))
 	instances = instances[:cnt]
 	if len(instances) == 0 {
 		return new(DummyPicker)
@@ -102,7 +104,9 @@ func (wb *weightedBalancer) createPicker(ctx context.Context, e discovery.Result
 		if balance {
 			picker = newRoundRobinPicker(instances)
 		} else {
-			picker = newWeightedRoundRobinPicker(instances)
+			klog.CtxErrorf(ctx, "KITEX-DEBUG: start newWeightedRoundRobinPicker")
+			picker = newWeightedRoundRobinPicker(ctx, instances)
+			klog.CtxErrorf(ctx, "KITEX-DEBUG: end newWeightedRoundRobinPicker")
 		}
 	default: // random
 		if balance {

pkg/loadbalance/weighted_round_robin.go

@@ -38,7 +38,7 @@ type wrrNode struct {
 	current int
 }
 
-func newWeightedRoundRobinPicker(instances []discovery.Instance) Picker {
+func newWeightedRoundRobinPicker(ctx context.Context, instances []discovery.Instance) Picker {
 	wrrp := new(WeightedRoundRobinPicker)
 	wrrp.iterator = newRound()
 
@@ -60,6 +60,7 @@ func newWeightedRoundRobinPicker(instances []discovery.Instance) Picker {
 	}
 	wrrp.vcapacity = uint64(totalWeight)
 	wrrp.vnodes = make([]discovery.Instance, wrrp.vcapacity)
+	klog.CtxErrorf(ctx, "KITEX-DEBUG: newWeightedRoundRobinPicker, vcapacity=%d", totalWeight)
 	wrrp.buildVirtualWrrNodes(wrrVNodesBatchSize)
 	return wrrp
 }
@@ -99,8 +100,9 @@ func (wp *WeightedRoundRobinPicker) Next(ctx context.Context, request interface{
 		vtarget = idx
 	}
 
-	klog.CtxErrorf(ctx, "KITEX-DEBUG: start buildVirtualWrrNodes")
+	klog.CtxErrorf(ctx, "KITEX-DEBUG: start buildVirtualWrrNodes, vcapacity=%d", wp.vcapacity)
 	wp.buildVirtualWrrNodes(vtarget)
+	klog.CtxErrorf(ctx, "KITEX-DEBUG: end buildVirtualWrrNodes")
 	return wp.vnodes[idx]
 }