From 1c2d88adfd07a25c8aa6f279d6279712d2797f31 Mon Sep 17 00:00:00 2001
From: smcio <shaun@darkwaves.io>
Date: Tue, 27 Jan 2026 20:08:56 +0000
Subject: [PATCH] some memory optimisations

---
 pkg/accountsdb/accountsdb.go     |  6 +++---
 pkg/replay/block.go              | 11 +++++++++++
 pkg/snapshot/manifest_decoder.go |  9 ++++++---
 3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/pkg/accountsdb/accountsdb.go b/pkg/accountsdb/accountsdb.go
index c6f701b6..1b578b5d 100644
--- a/pkg/accountsdb/accountsdb.go
+++ b/pkg/accountsdb/accountsdb.go
@@ -154,7 +154,7 @@ func (accountsDb *AccountsDb) CloseDb() {
 
 func (accountsDb *AccountsDb) InitCaches() {
 	var err error
-	accountsDb.VoteAcctCache, err = otter.MustBuilder[solana.PublicKey, *accounts.Account](5000).
+	accountsDb.VoteAcctCache, err = otter.MustBuilder[solana.PublicKey, *accounts.Account](2500).
 		Cost(func(key solana.PublicKey, acct *accounts.Account) uint32 {
 			return 1
 		}).
@@ -163,7 +163,7 @@ func (accountsDb *AccountsDb) InitCaches() {
 		panic(err)
 	}
 
-	accountsDb.ProgramCache, err = otter.MustBuilder[solana.PublicKey, *ProgramCacheEntry](5000).
+	accountsDb.ProgramCache, err = otter.MustBuilder[solana.PublicKey, *ProgramCacheEntry](2000).
 		Cost(func(key solana.PublicKey, progEntry *ProgramCacheEntry) uint32 {
 			return 1
 		}).
@@ -172,7 +172,7 @@ func (accountsDb *AccountsDb) InitCaches() {
 		panic(err)
 	}
 
-	accountsDb.CommonAcctsCache, err = otter.MustBuilder[solana.PublicKey, *accounts.Account](10000).
+	accountsDb.CommonAcctsCache, err = otter.MustBuilder[solana.PublicKey, *accounts.Account](5000).
 		Cost(func(key solana.PublicKey, acct *accounts.Account) uint32 {
 			return 1
 		}).
diff --git a/pkg/replay/block.go b/pkg/replay/block.go
index 5f132da2..93f64c22 100644
--- a/pkg/replay/block.go
+++ b/pkg/replay/block.go
@@ -1076,6 +1076,14 @@ func (t *persistedTracker) Get() (uint64, []byte) {
 	return slot, out
 }
 
+func nilifySnapshotManifest(manifest *snapshot.SnapshotManifest) {
+	manifest.Bank = nil
+	manifest.AccountsDb = nil
+	manifest.BankIncrementalSnapshotPersistence = nil
+	manifest.VersionedEpochStakes = nil
+	manifest.LtHash = nil
+}
+
 func ReplayBlocks(
 	ctx context.Context,
 	acctsDb *accountsdb.AccountsDb,
@@ -1335,6 +1343,9 @@ func ReplayBlocks(
 				// FRESH START: Use snapshot manifest
 				configErr = configureInitialBlock(acctsDb, block, snapshotManifest, replayCtx, epochSchedule, rpcc, rpcBackups)
 			}
+			// We're done with the SnapshotManifest object. Since these objects are quite large, we hint to the GC to free
+			// the object's contents by nil'ing the struct's members.
+			nilifySnapshotManifest(snapshotManifest)
 		} else {
 			configErr = configureBlock(block, replayCtx, lastSlotCtx, epochSchedule, rpcc, rpcBackups)
 		}
diff --git a/pkg/snapshot/manifest_decoder.go b/pkg/snapshot/manifest_decoder.go
index 34bace82..0c660314 100644
--- a/pkg/snapshot/manifest_decoder.go
+++ b/pkg/snapshot/manifest_decoder.go
@@ -255,10 +255,10 @@ type SerializableEpochRewardStatus struct {
 }
 
 type SnapshotManifest struct {
-	Bank                               DeserializableVersionedBank
-	AccountsDb                         AccountsDbFields
+	Bank                               *DeserializableVersionedBank
+	AccountsDb                         *AccountsDbFields
 	LamportsPerSignature               uint64
-	BankIncrementalSnapshotPersistence BankIncrementalSnapshotPersistence
+	BankIncrementalSnapshotPersistence *BankIncrementalSnapshotPersistence
 	EpochAccountHash                   [32]byte
 	VersionedEpochStakes               []VersionedEpochStakesPair
 	LtHash                             *lthash.LtHash
@@ -1413,12 +1413,14 @@ func (stakeRewards *SerializableStakeRewards) UnmarshalWithDecoder(decoder *bin.
 func (snapshot *SnapshotManifest) UnmarshalWithDecoder(decoder *bin.Decoder) error {
 	var err error
 
+	snapshot.Bank = new(DeserializableVersionedBank)
 	err = snapshot.Bank.UnmarshalWithDecoder(decoder)
 	if err != nil {
 		util.VerboseHandleError(err)
 		return err
 	}
 
+	snapshot.AccountsDb = new(AccountsDbFields)
 	err = snapshot.AccountsDb.UnmarshalWithDecoder(decoder)
 	if err != nil {
 		util.VerboseHandleError(err)
@@ -1442,6 +1444,7 @@ func (snapshot *SnapshotManifest) UnmarshalWithDecoder(decoder *bin.Decoder) err
 
 	if hasIncrementalSnapshotPersistence {
 		mlog.Log.Infof("hasIncrementalSnapshotPersistence")
+		snapshot.BankIncrementalSnapshotPersistence = new(BankIncrementalSnapshotPersistence)
 		err = snapshot.BankIncrementalSnapshotPersistence.UnmarshalWithDecoder(decoder)
 		if err != nil {
 			return nil