Try #4956:

common/types/activation.go

@@ -492,3 +492,8 @@ func ATXIDsToHashes(ids []ATXID) []Hash32 {
 	}
 	return hashes
 }
+
+type EpochActiveSet struct {
+	Epoch EpochID
+	Set   []ATXID `scale:"max=1000000"`
+}

config/mainnet.go

@@ -78,6 +78,7 @@ func MainnetConfig() Config {
 			// 1000 - is assumed minimal number of units
 			// 5000 - half of the expected poet ticks
 			MinimalActiveSetWeight: 1000 * 5000,
+			EmitEmptyActiveSet:     20000,
 		},
 		HARE: hareConfig.Config{
 			N:               200,

datastore/store.go

@@ -11,6 +11,7 @@ import (
 	"github.com/spacemeshos/go-spacemesh/common/types"
 	"github.com/spacemeshos/go-spacemesh/log"
 	"github.com/spacemeshos/go-spacemesh/sql"
+	"github.com/spacemeshos/go-spacemesh/sql/activesets"
 	"github.com/spacemeshos/go-spacemesh/sql/atxs"
 	"github.com/spacemeshos/go-spacemesh/sql/ballots"
 	"github.com/spacemeshos/go-spacemesh/sql/blocks"
@@ -320,6 +321,7 @@ const (
 	TXDB        Hint = "TXDB"
 	POETDB      Hint = "POETDB"
 	Malfeasance Hint = "malfeasance"
+	ActiveSet   Hint = "activeset"
 )
 
 // NewBlobStore returns a BlobStore.
@@ -369,6 +371,8 @@ func (bs *BlobStore) Get(hint Hint, key []byte) ([]byte, error) {
 		return poets.Get(bs.DB, ref)
 	case Malfeasance:
 		return identities.GetMalfeasanceBlob(bs.DB, key)
+	case ActiveSet:
+		return activesets.GetBlob(bs.DB, key)
 	}
 	return nil, fmt.Errorf("blob store not found %s", hint)
 }

fetch/fetch.go

@@ -210,6 +210,7 @@ type dataValidators struct {
 	atx         SyncValidator
 	poet        SyncValidator
 	ballot      SyncValidator
+	activeset   SyncValidator
 	block       SyncValidator
 	proposal    SyncValidator
 	txBlock     SyncValidator
@@ -222,6 +223,7 @@ func (f *Fetch) SetValidators(
 	atx SyncValidator,
 	poet SyncValidator,
 	ballot SyncValidator,
+	activeset SyncValidator,
 	block SyncValidator,
 	prop SyncValidator,
 	txBlock SyncValidator,
@@ -232,6 +234,7 @@ func (f *Fetch) SetValidators(
 		atx:         atx,
 		poet:        poet,
 		ballot:      ballot,
+		activeset:   activeset,
 		block:       block,
 		proposal:    prop,
 		txBlock:     txBlock,

fetch/fetch_test.go

@@ -37,6 +37,7 @@ type testFetch struct {
 	mMalH        *mocks.MockSyncValidator
 	mAtxH        *mocks.MockSyncValidator
 	mBallotH     *mocks.MockSyncValidator
+	mActiveSetH  *mocks.MockSyncValidator
 	mBlocksH     *mocks.MockSyncValidator
 	mProposalH   *mocks.MockSyncValidator
 	method       int
@@ -59,6 +60,7 @@ func createFetch(tb testing.TB) *testFetch {
 		mMalH:        mocks.NewMockSyncValidator(ctrl),
 		mAtxH:        mocks.NewMockSyncValidator(ctrl),
 		mBallotH:     mocks.NewMockSyncValidator(ctrl),
+		mActiveSetH:  mocks.NewMockSyncValidator(ctrl),
 		mBlocksH:     mocks.NewMockSyncValidator(ctrl),
 		mProposalH:   mocks.NewMockSyncValidator(ctrl),
 		mTxBlocksH:   mocks.NewMockSyncValidator(ctrl),
@@ -89,7 +91,7 @@ func createFetch(tb testing.TB) *testFetch {
 			OpnProtocol:      tf.mOpn2S,
 		}),
 		withHost(tf.mh))
-	tf.Fetch.SetValidators(tf.mAtxH, tf.mPoetH, tf.mBallotH, tf.mBlocksH, tf.mProposalH, tf.mTxBlocksH, tf.mTxProposalH, tf.mMalH)
+	tf.Fetch.SetValidators(tf.mAtxH, tf.mPoetH, tf.mBallotH, tf.mActiveSetH, tf.mBlocksH, tf.mProposalH, tf.mTxBlocksH, tf.mTxProposalH, tf.mMalH)
 	return tf
 }
 
@@ -415,7 +417,7 @@ func TestFetch_PeerDroppedWhenMessageResultsInValidationReject(t *testing.T) {
 
 	// We set a validatior just for atxs, this validator does not drop connections
 	vf := ValidatorFunc(func(context.Context, types.Hash32, peer.ID, []byte) error { return pubsub.ErrValidationReject })
-	fetcher.SetValidators(vf, nil, nil, nil, nil, nil, nil, nil)
+	fetcher.SetValidators(vf, nil, nil, nil, nil, nil, nil, nil, nil)
 
 	// Request an atx by hash
 	_, err = fetcher.getHash(ctx, types.Hash32{}, datastore.ATXDB, fetcher.validators.atx.HandleMessage)
@@ -430,7 +432,7 @@ func TestFetch_PeerDroppedWhenMessageResultsInValidationReject(t *testing.T) {
 	}
 
 	// Now wrap the atx validator with  DropPeerOnValidationReject and set it again
-	fetcher.SetValidators(ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(vf, h, lg)), nil, nil, nil, nil, nil, nil, nil)
+	fetcher.SetValidators(ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(vf, h, lg)), nil, nil, nil, nil, nil, nil, nil, nil)
 
 	// Request an atx by hash
 	_, err = fetcher.getHash(ctx, types.Hash32{}, datastore.ATXDB, fetcher.validators.atx.HandleMessage)

fetch/mesh_data.go

@@ -65,6 +65,12 @@ func (f *Fetch) getHashes(ctx context.Context, hashes []types.Hash32, hint datas
 	return errors.Join(errs, err)
 }
 
+// GetActiveSet downloads activeset.
+func (f *Fetch) GetActiveSet(ctx context.Context, set types.Hash32) error {
+	f.logger.WithContext(ctx).With().Debug("request active set", log.ShortStringer("id", set))
+	return f.getHashes(ctx, []types.Hash32{set}, datastore.ActiveSet, f.validators.activeset.HandleMessage)
+}
+
 // GetMalfeasanceProofs gets malfeasance proofs for the specified NodeIDs and validates them.
 func (f *Fetch) GetMalfeasanceProofs(ctx context.Context, ids []types.NodeID) error {
 	if len(ids) == 0 {

fetch/mesh_data_test.go

@@ -397,6 +397,19 @@ func TestGetATXs(t *testing.T) {
 	require.NoError(t, eg.Wait())
 }
 
+func TestGetActiveSet(t *testing.T) {
+	f := createFetch(t)
+	f.mActiveSetH.EXPECT().HandleMessage(gomock.Any(), gomock.Any(), gomock.Any(), gomock.Any()).Return(nil)
+
+	stop := make(chan struct{}, 1)
+	var eg errgroup.Group
+	startTestLoop(t, f.Fetch, &eg, stop)
+
+	require.NoError(t, f.GetActiveSet(context.Background(), types.Hash32{1, 2, 3}))
+	close(stop)
+	require.NoError(t, eg.Wait())
+}
+
 func TestGetPoetProof(t *testing.T) {
 	f := createFetch(t)
 	h := types.RandomHash()

miner/proposal_builder.go

@@ -19,6 +19,7 @@ import (
 	"github.com/spacemeshos/go-spacemesh/p2p/pubsub"
 	"github.com/spacemeshos/go-spacemesh/signing"
 	"github.com/spacemeshos/go-spacemesh/sql"
+	"github.com/spacemeshos/go-spacemesh/sql/activesets"
 	"github.com/spacemeshos/go-spacemesh/sql/ballots"
 	"github.com/spacemeshos/go-spacemesh/sql/certificates"
 	"github.com/spacemeshos/go-spacemesh/sql/layers"
@@ -65,6 +66,7 @@ type config struct {
 	layersPerEpoch     uint32
 	hdist              uint32
 	minActiveSetWeight uint64
+	emitEmptyActiveSet types.LayerID
 	nodeID             types.NodeID
 	networkDelay       time.Duration
 
@@ -139,6 +141,12 @@ func WithMinGoodAtxPct(pct int) Opt {
 	}
 }
 
+func WithEmitEmptyActiveSet(lid types.LayerID) Opt {
+	return func(pb *ProposalBuilder) {
+		pb.cfg.emitEmptyActiveSet = lid
+	}
+}
+
 func withOracle(o proposalOracle) Opt {
 	return func(pb *ProposalBuilder) {
 		pb.proposalOracle = o
@@ -257,6 +265,12 @@ func (pb *ProposalBuilder) createProposal(
 			Beacon:           beacon,
 			EligibilityCount: epochEligibility.Slots,
 		}
+		if err := activesets.Add(pb.cdb, ib.EpochData.ActiveSetHash, &types.EpochActiveSet{
+			Epoch: epoch,
+			Set:   epochEligibility.ActiveSet,
+		}); err != nil && !errors.Is(err, sql.ErrObjectExists) {
+			return nil, err
+		}
 	} else {
 		pb.logger.With().Debug("creating ballot with reference ballot (no active set)",
 			log.Context(ctx),
@@ -277,7 +291,7 @@ func (pb *ProposalBuilder) createProposal(
 			MeshHash: pb.decideMeshHash(ctx, layerID),
 		},
 	}
-	if p.EpochData != nil {
+	if p.EpochData != nil && layerID < pb.cfg.emitEmptyActiveSet {
 		p.ActiveSet = epochEligibility.ActiveSet
 	}
 	p.Ballot.Signature = pb.signer.Sign(signing.BALLOT, p.Ballot.SignedBytes())

miner/proposal_builder_test.go

@@ -21,6 +21,7 @@ import (
 	pubsubmocks "github.com/spacemeshos/go-spacemesh/p2p/pubsub/mocks"
 	"github.com/spacemeshos/go-spacemesh/signing"
 	"github.com/spacemeshos/go-spacemesh/sql"
+	"github.com/spacemeshos/go-spacemesh/sql/activesets"
 	"github.com/spacemeshos/go-spacemesh/sql/ballots"
 	"github.com/spacemeshos/go-spacemesh/sql/certificates"
 	"github.com/spacemeshos/go-spacemesh/sql/layers"
@@ -195,7 +196,7 @@ func TestBuilder_HandleLayer_MultipleProposals(t *testing.T) {
 			require.Equal(t, atxID, p.AtxID)
 			require.Equal(t, p.Layer, layerID)
 			require.NotNil(t, p.EpochData)
-			require.Equal(t, activeSet, types.ATXIDList(p.ActiveSet))
+			require.Empty(t, p.ActiveSet)
 			require.Equal(t, beacon, p.EpochData.Beacon)
 			require.Equal(t, ee.Slots, p.EpochData.EligibilityCount)
 			require.Equal(t, []types.TransactionID{tx1.ID}, p.TxIDs)
@@ -268,7 +269,8 @@ func TestBuilder_HandleLayer_OneProposal(t *testing.T) {
 			require.Equal(t, p.Layer, layerID)
 			require.NotNil(t, p.EpochData)
 			require.Equal(t, ee.Slots, p.EpochData.EligibilityCount)
-			require.Equal(t, activeSet, types.ATXIDList(p.ActiveSet))
+			require.Empty(t, p.ActiveSet)
+			require.Equal(t, activeSet.Hash(), p.EpochData.ActiveSetHash)
 			require.Equal(t, beacon, p.EpochData.Beacon)
 			require.Equal(t, []types.TransactionID{tx.ID}, p.TxIDs)
 			require.Equal(t, meshHash, p.MeshHash)
@@ -398,7 +400,11 @@ func TestBuilder_HandleLayer_NoRefBallot(t *testing.T) {
 			require.NoError(t, codec.Decode(data, &got))
 			require.Equal(t, types.EmptyBallotID, got.RefBallot)
 			require.Equal(t, types.EpochData{ActiveSetHash: activeSet.Hash(), Beacon: beacon, EligibilityCount: ee.Slots}, *got.EpochData)
-			require.Equal(t, activeSet, types.ATXIDList(got.ActiveSet))
+			require.Empty(t, got.ActiveSet)
+			saved, err := activesets.Get(b.cdb, activeSet.Hash())
+			require.NoError(t, err)
+			require.Equal(t, activeSet, types.ATXIDList(saved.Set))
+			require.Equal(t, got.Layer.GetEpoch(), saved.Epoch)
 			require.Equal(t, ee.Slots, got.EpochData.EligibilityCount)
 			return nil
 		})

node/node.go

@@ -888,6 +888,7 @@ func (app *App) initServices(ctx context.Context) error {
 		fetch.ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(atxHandler.HandleSyncedAtx, app.host, lg)),
 		fetch.ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(poetDb.ValidateAndStoreMsg, app.host, lg)),
 		fetch.ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(proposalListener.HandleSyncedBallot, app.host, lg)),
+		fetch.ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(proposalListener.HandleActiveSet, app.host, lg)),
 		fetch.ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(blockHandler.HandleSyncedBlock, app.host, lg)),
 		fetch.ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(proposalListener.HandleSyncedProposal, app.host, lg)),
 		fetch.ValidatorFunc(pubsub.DropPeerOnSyncValidationReject(app.txHandler.HandleBlockTransaction, app.host, lg)),