Add logs for build block times (#12452)

Co-authored-by: Nishant Das <nishdas93@gmail.com>

beacon-chain/rpc/prysm/v1alpha1/validator/proposer.go

@@ -50,6 +50,15 @@ func (vs *Server) GetBeaconBlock(ctx context.Context, req *ethpb.BlockRequest) (
 	defer span.End()
 	span.AddAttributes(trace.Int64Attribute("slot", int64(req.Slot)))
 
+	t, err := slots.ToTime(uint64(vs.TimeFetcher.GenesisTime().Unix()), req.Slot)
+	if err != nil {
+		log.WithError(err).Error("Could not convert slot to time")
+	}
+	log.WithFields(logrus.Fields{
+		"slot":               req.Slot,
+		"sinceSlotStartTime": time.Since(t),
+	}).Info("Begin building block")
+
 	// A syncing validator should not produce a block.
 	if vs.SyncChecker.Syncing() {
 		return nil, status.Error(codes.Unavailable, "Syncing to latest head, not ready to respond")
@@ -146,6 +155,12 @@ func (vs *Server) GetBeaconBlock(ctx context.Context, req *ethpb.BlockRequest) (
 	}
 	sBlk.SetStateRoot(sr)
 
+	log.WithFields(logrus.Fields{
+		"slot":               req.Slot,
+		"sinceSlotStartTime": time.Since(t),
+		"validator":          sBlk.Block().ProposerIndex(),
+	}).Info("Finished building block")
+
 	pb, err := sBlk.Block().Proto()
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "Could not convert block to proto: %v", err)

beacon-chain/rpc/prysm/v1alpha1/validator/proposer_bellatrix.go

@@ -219,9 +219,12 @@ func (vs *Server) getPayloadHeaderFromBuilder(ctx context.Context, slot primitiv
 	}
 
 	log.WithFields(logrus.Fields{
-		"value":         v.String(),
-		"builderPubKey": fmt.Sprintf("%#x", bid.Pubkey()),
-		"blockHash":     fmt.Sprintf("%#x", header.BlockHash()),
+		"value":              v.String(),
+		"builderPubKey":      fmt.Sprintf("%#x", bid.Pubkey()),
+		"blockHash":          fmt.Sprintf("%#x", header.BlockHash()),
+		"slot":               slot,
+		"validator":          idx,
+		"sinceSlotStartTime": time.Since(t),
 	}).Info("Received header with bid")
 
 	span.AddAttributes(