reducing e2e eth1lookahead

This PR adds the dependent root of the latest finalized checkpoint to
forkchoice since this node will be typically pruned upon finalization.

beacon-chain/blockchain/process_attestation_helpers.go

@@ -22,10 +22,7 @@ import (
 // The caller of this function must have a lock on forkchoice.
 func (s *Service) getRecentPreState(ctx context.Context, c *ethpb.Checkpoint) state.ReadOnlyBeaconState {
 	headEpoch := slots.ToEpoch(s.HeadSlot())
-	if c.Epoch < headEpoch {
-		return nil
-	}
-	if !s.cfg.ForkChoiceStore.IsCanonical([32]byte(c.Root)) {
+	if c.Epoch < headEpoch || c.Epoch == 0 {
 		return nil
 	}
 	// Only use head state if the head state is compatible with the target checkpoint.
@@ -33,11 +30,11 @@ func (s *Service) getRecentPreState(ctx context.Context, c *ethpb.Checkpoint) st
 	if err != nil {
 		return nil
 	}
-	headDependent, err := s.cfg.ForkChoiceStore.DependentRootForEpoch([32]byte(headRoot), c.Epoch)
+	headDependent, err := s.cfg.ForkChoiceStore.DependentRootForEpoch([32]byte(headRoot), c.Epoch-1)
 	if err != nil {
 		return nil
 	}
-	targetDependent, err := s.cfg.ForkChoiceStore.DependentRootForEpoch([32]byte(c.Root), c.Epoch)
+	targetDependent, err := s.cfg.ForkChoiceStore.DependentRootForEpoch([32]byte(c.Root), c.Epoch-1)
 	if err != nil {
 		return nil
 	}
@@ -53,7 +50,11 @@ func (s *Service) getRecentPreState(ctx context.Context, c *ethpb.Checkpoint) st
 		}
 		return st
 	}
-	// Otherwise we need to advance the head state to the start of the target epoch.
+	// At this point we can only have c.Epoch > headEpoch.
+	if !s.cfg.ForkChoiceStore.IsCanonical([32]byte(c.Root)) {
+		return nil
+	}
+	// Advance the head state to the start of the target epoch.
 	// This point can only be reached if c.Root == headRoot and c.Epoch > headEpoch.
 	slot, err := slots.EpochStart(c.Epoch)
 	if err != nil {

beacon-chain/blockchain/process_attestation_test.go

@@ -181,6 +181,123 @@ func TestService_GetRecentPreState(t *testing.T) {
 	require.NotNil(t, service.getRecentPreState(ctx, &ethpb.Checkpoint{Epoch: 1, Root: ckRoot}))
 }
 
+func TestService_GetRecentPreState_Epoch_0(t *testing.T) {
+	service, _ := minimalTestService(t)
+	ctx := t.Context()
+	require.IsNil(t, service.getRecentPreState(ctx, &ethpb.Checkpoint{}))
+}
+
+func TestService_GetRecentPreState_Old_Checkpoint(t *testing.T) {
+	service, _ := minimalTestService(t)
+	ctx := t.Context()
+	s, err := util.NewBeaconState()
+	require.NoError(t, err)
+	ckRoot := bytesutil.PadTo([]byte{'A'}, fieldparams.RootLength)
+	cp0 := &ethpb.Checkpoint{Epoch: 0, Root: ckRoot}
+	err = s.SetFinalizedCheckpoint(cp0)
+	require.NoError(t, err)
+
+	st, root, err := prepareForkchoiceState(ctx, 33, [32]byte(ckRoot), [32]byte{}, [32]byte{'R'}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, root))
+	service.head = &head{
+		root:  [32]byte(ckRoot),
+		state: s,
+		slot:  33,
+	}
+	require.IsNil(t, service.getRecentPreState(ctx, &ethpb.Checkpoint{}))
+}
+
+func TestService_GetRecentPreState_Same_DependentRoots(t *testing.T) {
+	service, _ := minimalTestService(t)
+	ctx := t.Context()
+	s, err := util.NewBeaconState()
+	require.NoError(t, err)
+	ckRoot := bytesutil.PadTo([]byte{'A'}, fieldparams.RootLength)
+	cp0 := &ethpb.Checkpoint{Epoch: 0, Root: ckRoot}
+
+	// Create a fork 31 <-- 32 <--- 64
+	//                 \---------33
+	// With the same dependent root at epoch 0 for a checkpoint at epoch 2
+	st, blk, err := prepareForkchoiceState(ctx, 31, [32]byte(ckRoot), [32]byte{}, [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	st, blk, err = prepareForkchoiceState(ctx, 32, [32]byte{'S'}, blk.Root(), [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	st, blk, err = prepareForkchoiceState(ctx, 64, [32]byte{'T'}, blk.Root(), [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	st, blk, err = prepareForkchoiceState(ctx, 33, [32]byte{'U'}, [32]byte(ckRoot), [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	cpRoot := blk.Root()
+
+	service.head = &head{
+		root:  [32]byte{'T'},
+		state: s,
+		slot:  64,
+	}
+	require.NotNil(t, service.getRecentPreState(ctx, &ethpb.Checkpoint{Epoch: 2, Root: cpRoot[:]}))
+}
+
+func TestService_GetRecentPreState_Different_DependentRoots(t *testing.T) {
+	service, _ := minimalTestService(t)
+	ctx := t.Context()
+	s, err := util.NewBeaconState()
+	require.NoError(t, err)
+	ckRoot := bytesutil.PadTo([]byte{'A'}, fieldparams.RootLength)
+	cp0 := &ethpb.Checkpoint{Epoch: 0, Root: ckRoot}
+
+	// Create a fork 30 <-- 31 <-- 32 <--- 64
+	//                 \---------33
+	// With the same dependent root at epoch 0 for a checkpoint at epoch 2
+	st, blk, err := prepareForkchoiceState(ctx, 30, [32]byte(ckRoot), [32]byte{}, [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	st, blk, err = prepareForkchoiceState(ctx, 31, [32]byte{'S'}, blk.Root(), [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	st, blk, err = prepareForkchoiceState(ctx, 32, [32]byte{'T'}, blk.Root(), [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	st, blk, err = prepareForkchoiceState(ctx, 64, [32]byte{'U'}, blk.Root(), [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	st, blk, err = prepareForkchoiceState(ctx, 33, [32]byte{'V'}, [32]byte(ckRoot), [32]byte{}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, blk))
+	cpRoot := blk.Root()
+
+	service.head = &head{
+		root:  [32]byte{'T'},
+		state: s,
+		slot:  64,
+	}
+	require.IsNil(t, service.getRecentPreState(ctx, &ethpb.Checkpoint{Epoch: 2, Root: cpRoot[:]}))
+}
+
+func TestService_GetRecentPreState_Different(t *testing.T) {
+	service, _ := minimalTestService(t)
+	ctx := t.Context()
+	s, err := util.NewBeaconState()
+	require.NoError(t, err)
+	ckRoot := bytesutil.PadTo([]byte{'A'}, fieldparams.RootLength)
+	cp0 := &ethpb.Checkpoint{Epoch: 0, Root: ckRoot}
+	err = s.SetFinalizedCheckpoint(cp0)
+	require.NoError(t, err)
+
+	st, root, err := prepareForkchoiceState(ctx, 33, [32]byte(ckRoot), [32]byte{}, [32]byte{'R'}, cp0, cp0)
+	require.NoError(t, err)
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, root))
+	service.head = &head{
+		root:  [32]byte(ckRoot),
+		state: s,
+		slot:  33,
+	}
+	require.IsNil(t, service.getRecentPreState(ctx, &ethpb.Checkpoint{}))
+}
+
 func TestService_GetAttPreState_Concurrency(t *testing.T) {
 	service, _ := minimalTestService(t)
 	ctx := t.Context()

beacon-chain/forkchoice/doubly-linked-tree/forkchoice.go

@@ -240,7 +240,7 @@ func (f *ForkChoice) IsViableForCheckpoint(cp *forkchoicetypes.Checkpoint) (bool
 	if node.slot == epochStart {
 		return true, nil
 	}
-	if !features.Get().DisableLastEpochTargets {
+	if !features.Get().IgnoreUnviableAttestations {
 		// Allow any node from the checkpoint epoch - 1 to be viable.
 		nodeEpoch := slots.ToEpoch(node.slot)
 		if nodeEpoch+1 == cp.Epoch {
@@ -642,8 +642,12 @@ func (f *ForkChoice) DependentRootForEpoch(root [32]byte, epoch primitives.Epoch
 	if !ok || node == nil {
 		return [32]byte{}, ErrNilNode
 	}
-	if slots.ToEpoch(node.slot) >= epoch && node.parent != nil {
-		node = node.parent
+	if slots.ToEpoch(node.slot) >= epoch {
+		if node.parent != nil {
+			node = node.parent
+		} else {
+			return f.store.finalizedDependentRoot, nil
+		}
 	}
 	return node.root, nil
 }

beacon-chain/forkchoice/doubly-linked-tree/store.go

@@ -212,6 +212,9 @@ func (s *Store) prune(ctx context.Context) error {
 		return nil
 	}
 
+	// Save the new finalized dependent root because it will be pruned
+	s.finalizedDependentRoot = finalizedNode.parent.root
+
 	// Prune nodeByRoot starting from root
 	if err := s.pruneFinalizedNodeByRootMap(ctx, s.treeRootNode, finalizedNode); err != nil {
 		return err

beacon-chain/forkchoice/doubly-linked-tree/store_test.go

@@ -465,6 +465,7 @@ func TestStore_TargetRootForEpoch(t *testing.T) {
 	ctx := t.Context()
 	f := setup(1, 1)
 
+	// Insert a block in slot 32
 	state, blk, err := prepareForkchoiceState(ctx, params.BeaconConfig().SlotsPerEpoch, [32]byte{'a'}, params.BeaconConfig().ZeroHash, params.BeaconConfig().ZeroHash, 1, 1)
 	require.NoError(t, err)
 	require.NoError(t, f.InsertNode(ctx, state, blk))
@@ -475,6 +476,7 @@ func TestStore_TargetRootForEpoch(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, dependent, [32]byte{})
 
+	// Insert a block in slot 33
 	state, blk1, err := prepareForkchoiceState(ctx, params.BeaconConfig().SlotsPerEpoch+1, [32]byte{'b'}, blk.Root(), params.BeaconConfig().ZeroHash, 1, 1)
 	require.NoError(t, err)
 	require.NoError(t, f.InsertNode(ctx, state, blk1))
@@ -488,7 +490,7 @@ func TestStore_TargetRootForEpoch(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, dependent, [32]byte{})
 
-	// Insert a block for the next epoch (missed slot 0)
+	// Insert a block for the next epoch (missed slot 0), slot 65
 
 	state, blk2, err := prepareForkchoiceState(ctx, 2*params.BeaconConfig().SlotsPerEpoch+1, [32]byte{'c'}, blk1.Root(), params.BeaconConfig().ZeroHash, 1, 1)
 	require.NoError(t, err)
@@ -509,6 +511,7 @@ func TestStore_TargetRootForEpoch(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, dependent, blk1.Root())
 
+	// Insert a block at slot 66
 	state, blk3, err := prepareForkchoiceState(ctx, 2*params.BeaconConfig().SlotsPerEpoch+2, [32]byte{'d'}, blk2.Root(), params.BeaconConfig().ZeroHash, 1, 1)
 	require.NoError(t, err)
 	require.NoError(t, f.InsertNode(ctx, state, blk3))
@@ -533,8 +536,11 @@ func TestStore_TargetRootForEpoch(t *testing.T) {
 	dependent, err = f.DependentRoot(1)
 	require.NoError(t, err)
 	require.Equal(t, [32]byte{}, dependent)
+	dependent, err = f.DependentRoot(2)
+	require.NoError(t, err)
+	require.Equal(t, blk1.Root(), dependent)
 
-	// Insert a block for next epoch (slot 0 present)
+	// Insert a block for the next epoch, slot 96 (descends from finalized at slot 33)
 	state, blk4, err := prepareForkchoiceState(ctx, 3*params.BeaconConfig().SlotsPerEpoch, [32]byte{'e'}, blk1.Root(), params.BeaconConfig().ZeroHash, 1, 1)
 	require.NoError(t, err)
 	require.NoError(t, f.InsertNode(ctx, state, blk4))
@@ -551,6 +557,7 @@ func TestStore_TargetRootForEpoch(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, dependent, blk1.Root())
 
+	// Insert a block at slot 97
 	state, blk5, err := prepareForkchoiceState(ctx, 3*params.BeaconConfig().SlotsPerEpoch+1, [32]byte{'f'}, blk4.Root(), params.BeaconConfig().ZeroHash, 1, 1)
 	require.NoError(t, err)
 	require.NoError(t, f.InsertNode(ctx, state, blk5))
@@ -600,12 +607,16 @@ func TestStore_TargetRootForEpoch(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, target, blk1.Root())
 
-	// Prune finalization
+	// Prune finalization, finalize the block at slot 96
 	s.finalizedCheckpoint.Root = blk4.Root()
 	require.NoError(t, s.prune(ctx))
 	target, err = f.TargetRootForEpoch(blk4.Root(), 3)
 	require.NoError(t, err)
 	require.Equal(t, blk4.Root(), target)
+	// Dependent root for the finalized block should be the root of the pruned block at slot 33
+	dependent, err = f.DependentRootForEpoch(blk4.Root(), 3)
+	require.NoError(t, err)
+	require.Equal(t, blk1.Root(), dependent)
 }
 
 func TestStore_DependentRootForEpoch(t *testing.T) {

beacon-chain/forkchoice/doubly-linked-tree/types.go

@@ -31,6 +31,7 @@ type Store struct {
 	proposerBoostRoot             [fieldparams.RootLength]byte           // latest block root that was boosted after being received in a timely manner.
 	previousProposerBoostRoot     [fieldparams.RootLength]byte           // previous block root that was boosted after being received in a timely manner.
 	previousProposerBoostScore    uint64                                 // previous proposer boosted root score.
+	finalizedDependentRoot        [fieldparams.RootLength]byte           // dependent root at finalized checkpoint.
 	committeeWeight               uint64                                 // tracks the total active validator balance divided by the number of slots per Epoch.
 	treeRootNode                  *Node                                  // the root node of the store tree.
 	headNode                      *Node                                  // last head Node

beacon-chain/rpc/lookup/blocker.go

@@ -450,7 +450,7 @@ func (p *BeaconDbBlocker) blobsDataFromStoredDataColumns(root [fieldparams.RootL
 	if count < peerdas.MinimumColumnCountToReconstruct() {
 		// There is no way to reconstruct the data columns.
 		return nil, &core.RpcError{
-			Err:    errors.Errorf("the node does not custody enough data columns to reconstruct blobs - please start the beacon node with the `--%s` flag to ensure this call to succeed, or retry later if it is already the case", flags.Supernode.Name),
+			Err:    errors.Errorf("the node does not custody enough data columns to reconstruct blobs - please start the beacon node with the `--%s` flag to ensure this call to succeed", flags.SemiSupernode.Name),
 			Reason: core.NotFound,
 		}
 	}

beacon-chain/sync/metrics.go

@@ -157,6 +157,12 @@ var (
 			Help: "Time for gossiped blob sidecars to arrive",
 		},
 	)
+	dataColumnSidecarArrivalGossipSummary = promauto.NewSummary(
+		prometheus.SummaryOpts{
+			Name: "gossip_data_column_sidecar_arrival_milliseconds",
+			Help: "Time for gossiped data column sidecars to arrive",
+		},
+	)
 	blobSidecarVerificationGossipSummary = promauto.NewSummary(
 		prometheus.SummaryOpts{
 			Name: "gossip_blob_sidecar_verification_milliseconds",

beacon-chain/sync/validate_data_column.go

@@ -191,6 +191,7 @@ func (s *Service) validateDataColumn(ctx context.Context, pid peer.ID, msg *pubs
 
 	sinceSlotStartTime := receivedTime.Sub(startTime)
 	validationTime := s.cfg.clock.Now().Sub(receivedTime)
+	dataColumnSidecarArrivalGossipSummary.Observe(float64(sinceSlotStartTime.Milliseconds()))
 	dataColumnSidecarVerificationGossipHistogram.Observe(float64(validationTime.Milliseconds()))
 
 	peerGossipScore := s.cfg.p2p.Peers().Scorers().GossipScorer().Score(pid)

changelog/james-prysm_reduce-lookahead-e2e.md

@@ -0,0 +1,3 @@
+### Changed
+
+- reduced eth1lookahead value from 8 to 1 since e2e only supports post merge(bellatrix), this will remove the error "Beacon node is not respecting the follow distance. EL client is syncing."

changelog/manu-logs-beacon-chain.md

@@ -0,0 +1,3 @@
+### Changed
+
+- `blobsDataFromStoredDataColumns`: Ask the use to use the `--supernode` flag and shorten the error mesage.

changelog/potuz_finalized_deproot.md

@@ -0,0 +1,3 @@
+### Added
+
+- Track the dependent root of the latest finalized checkpoint in forkchoice.

changelog/potuz_use_head_more_cases.md

@@ -0,0 +1,3 @@
+### Fixed
+
+- Use head state to validate attestations for old blocks if they are compatible.

changelog/terence_data-column-arrival-metric.md

@@ -0,0 +1,2 @@
+### Added
+- prometheus summary `gossip_data_column_sidecar_arrival_milliseconds` to track data column sidecar arrival latency since slot start.

changelog/terence_ignore-unviable-attestations-flag.md

@@ -0,0 +1,2 @@
+### Changed
+- Introduced flag `--ignore-unviable-attestations` (replaces and deprecates `--disable-last-epoch-targets`) to drop attestations whose target state is not viable; default remains to process them unless explicitly enabled.

config/features/config.go

@@ -71,7 +71,7 @@ type Flags struct {
 
 	DisableResourceManager     bool // Disables running the node with libp2p's resource manager.
 	DisableStakinContractCheck bool // Disables check for deposit contract when proposing blocks
-	DisableLastEpochTargets    bool // Disables processing of states for attestations to old blocks.
+	IgnoreUnviableAttestations bool // Ignore attestations whose target state is not viable (avoids lagging-node DoS).
 
 	EnableVerboseSigVerification bool // EnableVerboseSigVerification specifies whether to verify individual signature if batch verification fails
 
@@ -281,9 +281,11 @@ func ConfigureBeaconChain(ctx *cli.Context) error {
 		logEnabled(blacklistRoots)
 		cfg.BlacklistedRoots = parseBlacklistedRoots(ctx.StringSlice(blacklistRoots.Name))
 	}
-	if ctx.IsSet(disableLastEpochTargets.Name) {
-		logEnabled(disableLastEpochTargets)
-		cfg.DisableLastEpochTargets = true
+
+	cfg.IgnoreUnviableAttestations = false
+	if ctx.IsSet(ignoreUnviableAttestations.Name) && ctx.Bool(ignoreUnviableAttestations.Name) {
+		logEnabled(ignoreUnviableAttestations)
+		cfg.IgnoreUnviableAttestations = true
 	}
 
 	if ctx.IsSet(EnableStateDiff.Name) {

config/features/deprecated_flags.go

@@ -25,4 +25,6 @@ var upcomingDeprecation = []cli.Flag{
 
 // deprecatedBeaconFlags contains flags that are still used by other components
 // and therefore cannot be added to deprecatedFlags
-var deprecatedBeaconFlags = []cli.Flag{}
+var deprecatedBeaconFlags = []cli.Flag{
+	deprecatedDisableLastEpochTargets,
+}

config/features/flags.go

@@ -201,10 +201,15 @@ var (
 		Usage: "(Work in progress): Enables the web portal for the validator client.",
 		Value: false,
 	}
-	// disableLastEpochTargets is a flag to disable processing of attestations for old blocks.
-	disableLastEpochTargets = &cli.BoolFlag{
+	// deprecatedDisableLastEpochTargets is a flag to disable processing of attestations for old blocks.
+	deprecatedDisableLastEpochTargets = &cli.BoolFlag{
 		Name:  "disable-last-epoch-targets",
-		Usage: "Disables processing of last epoch targets.",
+		Usage: "Deprecated: disables processing of last epoch targets.",
+	}
+	// ignoreUnviableAttestations flag to skip attestations whose target state is not viable with respect to head (from lagging nodes).
+	ignoreUnviableAttestations = &cli.BoolFlag{
+		Name:  "ignore-unviable-attestations",
+		Usage: "Ignores attestations whose target state is not viable with respect to the current head (avoid expensive state replay from lagging attesters).",
 	}
 )
 
@@ -251,6 +256,7 @@ var BeaconChainFlags = combinedFlags([]cli.Flag{
 	disableStakinContractCheck,
 	SaveFullExecutionPayloads,
 	enableStartupOptimistic,
+	ignoreUnviableAttestations,
 	enableFullSSZDataLogging,
 	disableVerboseSigVerification,
 	prepareAllPayloads,
@@ -266,7 +272,6 @@ var BeaconChainFlags = combinedFlags([]cli.Flag{
 	enableExperimentalAttestationPool,
 	forceHeadFlag,
 	blacklistRoots,
-	disableLastEpochTargets,
 }, deprecatedBeaconFlags, deprecatedFlags, upcomingDeprecation)
 
 func combinedFlags(flags ...[]cli.Flag) []cli.Flag {

config/params/testdata/e2e_config.yaml

@@ -64,8 +64,9 @@ SECONDS_PER_ETH1_BLOCK: 2 # Override for e2e tests
 MIN_VALIDATOR_WITHDRAWABILITY_DELAY: 1
 # [customized] higher frequency of committee turnover and faster time to acceptable voluntary exit
 SHARD_COMMITTEE_PERIOD: 4 # Override for e2e tests
-# [customized] process deposits more quickly, but insecure
-ETH1_FOLLOW_DISTANCE: 8 # Override for e2e tests
+# [customized] Post-merge, the follow distance is less critical since finality is guaranteed by the beacon chain.
+# Setting to 1 avoids timing issues during e2e startup when the EL has few blocks.
+ETH1_FOLLOW_DISTANCE: 1 # Override for e2e tests
 
 
 # Validator cycle

config/params/testnet_e2e_config.go

@@ -17,7 +17,9 @@ const (
 func E2ETestConfig() *BeaconChainConfig {
 	e2eConfig := MinimalSpecConfig()
 	e2eConfig.DepositContractAddress = "0x4242424242424242424242424242424242424242"
-	e2eConfig.Eth1FollowDistance = 8
+	// Post-merge, the follow distance is less critical since finality is guaranteed by the beacon chain.
+	// Setting to 1 avoids timing issues during e2e startup when the EL has few blocks.
+	e2eConfig.Eth1FollowDistance = 1
 
 	// Misc.
 	e2eConfig.MinGenesisActiveValidatorCount = 256
@@ -73,7 +75,9 @@ func E2ETestConfig() *BeaconChainConfig {
 func E2EMainnetTestConfig() *BeaconChainConfig {
 	e2eConfig := MainnetConfig()
 	e2eConfig.DepositContractAddress = "0x4242424242424242424242424242424242424242"
-	e2eConfig.Eth1FollowDistance = 8
+	// Post-merge, the follow distance is less critical since finality is guaranteed by the beacon chain.
+	// Setting to 1 avoids timing issues during e2e startup when the EL has few blocks.
+	e2eConfig.Eth1FollowDistance = 1
 
 	// Misc.
 	e2eConfig.MinGenesisActiveValidatorCount = 256