add option for hotstore message retention

blockstore/splitstore/splitstore.go

@@ -71,6 +71,13 @@ type Config struct {
 	// which skips moving (as it is a noop, but still takes time to read all the cold objects)
 	// and directly purges cold blocks.
 	DiscardColdBlocks bool
+
+	// HotstoreMessageRetention indicates the hotstore retention policy for messages.
+	// It has the following semantics:
+	// - a value of 0 will only retain messages within the compaction boundary (4 finalities)
+	// - a positive integer indicates the number of finalities, outside the compaction boundary,
+	//   for which messages will be retained in the hotstore.
+	HotStoreMessageRetention uint64
 }
 
 // ChainAccessor allows the Splitstore to access the chain. It will most likely

node/config/def.go

@@ -251,6 +251,8 @@ type Splitstore struct {
 	ColdStoreType string
 	HotStoreType  string
 	MarkSetType   string
+
+	HotStoreMessageRetention uint64
 }
 
 // // Full Node

node/modules/blockstore.go

@@ -78,8 +78,9 @@ func SplitBlockstore(cfg *config.Chainstore) func(lc fx.Lifecycle, r repo.Locked
 		}
 
 		cfg := &splitstore.Config{
-			MarkSetType:       cfg.Splitstore.MarkSetType,
-			DiscardColdBlocks: cfg.Splitstore.ColdStoreType == "discard",
+			MarkSetType:              cfg.Splitstore.MarkSetType,
+			DiscardColdBlocks:        cfg.Splitstore.ColdStoreType == "discard",
+			HotStoreMessageRetention: cfg.Splitstore.HotStoreMessageRetention,
 		}
 		ss, err := splitstore.Open(path, ds, hot, cold, cfg)
 		if err != nil {