diff --git a/chain/store/splitstore/liveset.go b/chain/store/splitstore/liveset.go
index 6b64a3a56..62a5d6913 100644
--- a/chain/store/splitstore/liveset.go
+++ b/chain/store/splitstore/liveset.go
@@ -17,7 +17,7 @@ type LiveSet interface {
 var markBytes = []byte{}
 
 type LiveSetEnv interface {
-	NewLiveSet(name string) (LiveSet, error)
+	NewLiveSet(name string, sizeHint int64) (LiveSet, error)
 	Close() error
 }
 
diff --git a/chain/store/splitstore/liveset_bloom.go b/chain/store/splitstore/liveset_bloom.go
index f4d28a5dd..9fc3503b3 100644
--- a/chain/store/splitstore/liveset_bloom.go
+++ b/chain/store/splitstore/liveset_bloom.go
@@ -30,14 +30,19 @@ func NewBloomLiveSetEnv() (*BloomLiveSetEnv, error) {
 	return &BloomLiveSetEnv{}, nil
 }
 
-func (e *BloomLiveSetEnv) NewLiveSet(name string) (LiveSet, error) {
+func (e *BloomLiveSetEnv) NewLiveSet(name string, sizeHint int64) (LiveSet, error) {
+	size := int64(BloomFilterSize)
+	for size < sizeHint {
+		size += BloomFilterSize
+	}
+
 	salt := make([]byte, 4)
 	_, err := rand.Read(salt) //nolint
 	if err != nil {
 		return nil, xerrors.Errorf("error reading salt: %w", err)
 	}
 
-	bf, err := bbloom.New(float64(BloomFilterSize), float64(BloomFilterProbability))
+	bf, err := bbloom.New(float64(size), float64(BloomFilterProbability))
 	if err != nil {
 		return nil, xerrors.Errorf("error creating bloom filter: %w", err)
 	}
diff --git a/chain/store/splitstore/liveset_bolt.go b/chain/store/splitstore/liveset_bolt.go
index 0d6d7cd2e..8c68d6a4a 100644
--- a/chain/store/splitstore/liveset_bolt.go
+++ b/chain/store/splitstore/liveset_bolt.go
@@ -35,7 +35,7 @@ func NewBoltLiveSetEnv(path string) (*BoltLiveSetEnv, error) {
 	return &BoltLiveSetEnv{db: db}, nil
 }
 
-func (e *BoltLiveSetEnv) NewLiveSet(name string) (LiveSet, error) {
+func (e *BoltLiveSetEnv) NewLiveSet(name string, hint int64) (LiveSet, error) {
 	bucketId := []byte(name)
 	err := e.db.Update(func(tx *bolt.Tx) error {
 		_, err := tx.CreateBucketIfNotExists(bucketId)
diff --git a/chain/store/splitstore/liveset_lmdb.go b/chain/store/splitstore/liveset_lmdb.go
index f41907207..e8123f104 100644
--- a/chain/store/splitstore/liveset_lmdb.go
+++ b/chain/store/splitstore/liveset_lmdb.go
@@ -57,7 +57,7 @@ func NewLMDBLiveSetEnv(path string) (*LMDBLiveSetEnv, error) {
 	return &LMDBLiveSetEnv{env: env}, nil
 }
 
-func (e *LMDBLiveSetEnv) NewLiveSet(name string) (LiveSet, error) {
+func (e *LMDBLiveSetEnv) NewLiveSet(name string, hint int64) (LiveSet, error) {
 	return NewLMDBLiveSet(e.env, name+".lmdb")
 }
 
diff --git a/chain/store/splitstore/splitstore.go b/chain/store/splitstore/splitstore.go
index 8001f792c..e20615e68 100644
--- a/chain/store/splitstore/splitstore.go
+++ b/chain/store/splitstore/splitstore.go
@@ -75,6 +75,8 @@ type SplitStore struct {
 	snoop TrackingStore
 
 	env LiveSetEnv
+
+	liveSetSize int64
 }
 
 var _ bstore.Blockstore = (*SplitStore)(nil)
@@ -328,6 +330,15 @@ func (s *SplitStore) HeadChange(revert, apply []*types.TipSet) error {
 
 // Compaction/GC Algorithm
 func (s *SplitStore) compact() {
+	if s.liveSetSize == 0 {
+		start := time.Now()
+		log.Info("estimating live set size")
+		s.estimateLiveSetSize()
+		log.Infow("estimating live set size done", "took", time.Since(start), "size", s.liveSetSize)
+	} else {
+		log.Infow("current live set size estimate", "size", s.liveSetSize)
+	}
+
 	if s.fullCompaction {
 		s.compactFull()
 	} else {
@@ -335,6 +346,24 @@ func (s *SplitStore) compact() {
 	}
 }
 
+func (s *SplitStore) estimateLiveSetSize() {
+	s.mx.Lock()
+	curTs := s.curTs
+	s.mx.Unlock()
+
+	s.liveSetSize = 0
+	err := s.cs.WalkSnapshot(context.Background(), curTs, 1, s.skipOldMsgs, s.skipMsgReceipts,
+		func(cid cid.Cid) error {
+			s.liveSetSize++
+			return nil
+		})
+
+	if err != nil {
+		// TODO do something better here
+		panic(err)
+	}
+}
+
 func (s *SplitStore) compactSimple() {
 	s.mx.Lock()
 	curTs := s.curTs
@@ -344,7 +373,7 @@ func (s *SplitStore) compactSimple() {
 
 	log.Infow("running simple compaction", "currentEpoch", curTs.Height(), "baseEpoch", s.baseEpoch, "coldEpoch", coldEpoch)
 
-	coldSet, err := s.env.NewLiveSet("cold")
+	coldSet, err := s.env.NewLiveSet("cold", s.liveSetSize)
 	if err != nil {
 		// TODO do something better here
 		panic(err)
@@ -361,8 +390,10 @@ func (s *SplitStore) compactSimple() {
 		panic(err)
 	}
 
+	count := int64(0)
 	err = s.cs.WalkSnapshot(context.Background(), coldTs, 1, s.skipOldMsgs, s.skipMsgReceipts,
 		func(cid cid.Cid) error {
+			count++
 			return coldSet.Mark(cid)
 		})
 
@@ -371,6 +402,10 @@ func (s *SplitStore) compactSimple() {
 		panic(err)
 	}
 
+	if count > s.liveSetSize {
+		s.liveSetSize = count
+	}
+
 	log.Infow("marking done", "took", time.Since(startMark))
 
 	// 2. move cold unreachable objects to the coldstore
@@ -519,14 +554,14 @@ func (s *SplitStore) compactFull() {
 
 	// create two live sets, one for marking the cold finality region
 	// and one for marking the hot region
-	hotSet, err := s.env.NewLiveSet("hot")
+	hotSet, err := s.env.NewLiveSet("hot", s.liveSetSize)
 	if err != nil {
 		// TODO do something better here
 		panic(err)
 	}
 	defer hotSet.Close() //nolint:errcheck
 
-	coldSet, err := s.env.NewLiveSet("cold")
+	coldSet, err := s.env.NewLiveSet("cold", s.liveSetSize)
 	if err != nil {
 		// TODO do something better here
 		panic(err)
@@ -538,8 +573,10 @@ func (s *SplitStore) compactFull() {
 	startMark := time.Now()
 
 	// Phase 1a: mark all reachable CIDs in the hot range
+	count := int64(0)
 	err = s.cs.WalkSnapshot(context.Background(), curTs, epoch-coldEpoch, s.skipOldMsgs, s.skipMsgReceipts,
 		func(cid cid.Cid) error {
+			count++
 			return hotSet.Mark(cid)
 		})
 
@@ -548,6 +585,10 @@ func (s *SplitStore) compactFull() {
 		panic(err)
 	}
 
+	if count > s.liveSetSize {
+		s.liveSetSize = count
+	}
+
 	// Phase 1b: mark all reachable CIDs in the cold range
 	coldTs, err := s.cs.GetTipsetByHeight(context.Background(), coldEpoch, curTs, true)
 	if err != nil {
@@ -555,8 +596,10 @@ func (s *SplitStore) compactFull() {
 		panic(err)
 	}
 
+	count = 0
 	err = s.cs.WalkSnapshot(context.Background(), coldTs, CompactionCold, s.skipOldMsgs, s.skipMsgReceipts,
 		func(cid cid.Cid) error {
+			count++
 			return coldSet.Mark(cid)
 		})
 
@@ -565,6 +608,10 @@ func (s *SplitStore) compactFull() {
 		panic(err)
 	}
 
+	if count > s.liveSetSize {
+		s.liveSetSize = count
+	}
+
 	log.Infow("marking done", "took", time.Since(startMark))
 
 	// Phase 2: sweep cold objects: