Enable async IO by default (#6222)

Author: StefanBratanov

CHANGELOG.md

@@ -21,6 +21,7 @@ For information on changes in released versions of Teku, see the [releases page]
 - The `--initial-state` and `--eth1-deposit-contract-address` options has been removed from the `validator-client` subcommand. They have been ignored for some time but are now completely removed.
 
 ### Additions and Improvements
+- Enables asynchronous database updates by default. This ensures slow disk access or LevelDB compactions don't cause delays in the beacon node.
 - Make Validator Client connect to a failover event stream (if failovers are configured) when the current Beacon Node is not synced
 - Detect Lodestar clients in `libp2p_connected_peers_current` metrics
 - Reduce CPU and Memory consumption in shuffling, which will improve epoch transition performance

storage/src/main/java/tech/pegasys/teku/storage/store/StoreConfig.java

@@ -25,7 +25,7 @@ public class StoreConfig {
   public static final int DEFAULT_BLOCK_CACHE_SIZE = 32;
   public static final int DEFAULT_CHECKPOINT_STATE_CACHE_SIZE = 20;
   public static final int DEFAULT_HOT_STATE_PERSISTENCE_FREQUENCY_IN_EPOCHS = 2;
-  public static final boolean DEFAULT_ASYNC_STORAGE_ENABLED = false;
+  public static final boolean DEFAULT_ASYNC_STORAGE_ENABLED = true;
 
   private final int stateCacheSize;
   private final int blockCacheSize;

storage/src/test/java/tech/pegasys/teku/storage/server/kvstore/DatabaseTest.java

@@ -128,7 +128,8 @@ public void setup() throws IOException {
 
   private void initialize(final DatabaseContext context, final StateStorageMode storageMode)
       throws IOException {
-    createStorageSystem(context, storageMode, StoreConfig.createDefault(), false);
+    final StoreConfig config = StoreConfig.builder().asyncStorageEnabled(false).build();
+    createStorageSystem(context, storageMode, config, false);
 
     // Initialize genesis store
     initGenesis();

storage/src/test/java/tech/pegasys/teku/storage/store/StoreTest.java

@@ -251,7 +251,12 @@ public void retrieveFinalizedCheckpointAndState() {
   }
 
   public void testApplyChangesWhenTransactionCommits(final boolean withInterleavedTransaction) {
-    final UpdatableStore store = createGenesisStore();
+    final StoreConfig configWithAsyncIoDisabled =
+        StoreConfig.builder().asyncStorageEnabled(false).build();
+    final UpdatableStore store =
+        withInterleavedTransaction
+            ? createGenesisStore(configWithAsyncIoDisabled)
+            : createGenesisStore();
     final UInt64 epoch3 = UInt64.valueOf(4);
     final UInt64 epoch3Slot = spec.computeStartSlotAtEpoch(epoch3);
     chainBuilder.generateBlocksUpToSlot(epoch3Slot);