chore: add badger constraints on index and block cache (#3209)

* add sustainable badger configs

* remove blockcache size

* changelog

Author: tac0turtle

CHANGELOG.md

@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 - Avoid evicting yet to be processed heights [#3204](https://github.com/evstack/ev-node/pull/3204)
+- Bound Badger index cache memory to prevent growth with chain length [3209](https://github.com/evstack/ev-node/pull/3209)
 - Refetch latest da height instead of da height +1 when P2P is offline [#3201](https://github.com/evstack/ev-node/pull/3201)
 - Fix race on startup sync. [#3162](https://github.com/evstack/ev-node/pull/3162)
 - Strict raft state. [#3167](https://github.com/evstack/ev-node/pull/3167)

pkg/store/badger_options.go

@@ -6,11 +6,20 @@ import (
 	badger4 "github.com/ipfs/go-ds-badger4"
 )
 
+const (
+	// DefaultBadgerIndexCacheSize bounds Badger's table index and bloom filter
+	// cache to avoid growth with chain length.
+	DefaultBadgerIndexCacheSize int64 = 256 << 20 // 256 MiB
+)
+
 // BadgerOptions returns ev-node tuned Badger options for the node workload.
 // These defaults favor write throughput for append-heavy usage.
 func BadgerOptions() *badger4.Options {
 	opts := badger4.DefaultOptions
 
+	// Bound Badger-owned caches explicitly instead of inheriting a large block
+	// cache and an unbounded index cache from the upstream defaults.
+	opts.Options = opts.WithIndexCacheSize(DefaultBadgerIndexCacheSize)
 	// Disable conflict detection to reduce write overhead; ev-node does not rely
 	// on Badger's multi-writer conflict checks for correctness.
 	opts.Options = opts.WithDetectConflicts(false)