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Signed-off-by: OneSizeFitsQuorum <[email protected]>

Author: OneSizeFitsQuorum

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/wal/allocation/AbstractNodeAllocationStrategy.java

@@ -49,6 +49,8 @@ protected AbstractNodeAllocationStrategy() {
           new FolderManager(
               Arrays.asList(commonConfig.getWalDirs()), DirectoryStrategyType.SEQUENCE_STRATEGY);
     } catch (DiskSpaceInsufficientException e) {
+      // folderManager remains null when disk space is insufficient during initialization
+      // It will be lazily initialized later when disk space becomes available
       logger.error(
           "Fail to create wal node allocation strategy because all disks of wal folders are full.",
           e);
@@ -57,6 +59,9 @@ protected AbstractNodeAllocationStrategy() {
 
   protected synchronized IWALNode createWALNode(String identifier) {
     try {
+      // Lazy initialization of folderManager: if it was null during constructor
+      // (due to insufficient disk space), try to initialize it now when disk space
+      // might have become available
       if (folderManager == null) {
         folderManager =
             new FolderManager(