Improve error handling

op-node/rollup/derive/pipeline.go

@@ -2,6 +2,7 @@ package derive
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 
@@ -205,7 +206,7 @@ func (dp *DerivationPipeline) Step(ctx context.Context) error {
 	if err := dp.eng.Step(ctx); err == io.EOF {
 		// If every stage has returned io.EOF, try to advance the L1 Origin
 		return dp.traversal.AdvanceL1Block(ctx)
-	} else if err == EngineP2PSyncing {
+	} else if errors.Is(err, EngineP2PSyncing) {
 		return err
 	} else if err != nil {
 		return fmt.Errorf("engine stage failed: %w", err)

op-node/rollup/driver/state.go

@@ -313,11 +313,16 @@ func (s *Driver) eventLoop() {
 			s.log.Debug("Derivation process step", "onto_origin", s.derivation.Origin(), "attempts", stepAttempts)
 			err := s.derivation.Step(context.Background())
 			stepAttempts += 1 // count as attempt by default. We reset to 0 if we are making healthy progress.
-			if err == io.EOF || (err != nil && errors.Is(err, derive.EngineP2PSyncing)) {
+			if err == io.EOF {
 				s.log.Debug("Derivation process went idle", "progress", s.derivation.Origin(), "err", err)
 				stepAttempts = 0
 				s.metrics.SetDerivationIdle(true)
 				continue
+			} else if err != nil && errors.Is(err, derive.EngineP2PSyncing) {
+				s.log.Debug("Derivation process went idle because the engine is syncing", "progress", s.derivation.Origin(), "sync_target", s.derivation.EngineSyncTarget(), "err", err)
+				stepAttempts = 0
+				s.metrics.SetDerivationIdle(true)
+				continue
 			} else if err != nil && errors.Is(err, derive.ErrReset) {
 				// If the pipeline corrupts, e.g. due to a reorg, simply reset it
 				s.log.Warn("Derivation pipeline is reset", "err", err)