apache/hadoop · error · UnsupportedOperationException

Cannot truncate lazy persist file <src>

Error message

Cannot truncate lazy persist file <src>

What it means

Error "Cannot truncate lazy persist file <src>" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirTruncateOp.java:101

    try {
      iip = fsd.resolvePath(pc, srcArg, DirOp.WRITE);
      src = iip.getPath();
      if (fsd.isPermissionEnabled()) {
        fsd.checkPathAccess(pc, iip, FsAction.WRITE);
      }
      INodeFile file = INodeFile.valueOf(iip.getLastINode(), src);

      // not support truncating file with striped blocks
      if (file.isStriped()) {
        throw new UnsupportedOperationException(
            "Cannot truncate file with striped block " + src);
      }

      final BlockStoragePolicy lpPolicy = fsd.getBlockManager()
          .getStoragePolicy("LAZY_PERSIST");

      if (lpPolicy != null && lpPolicy.getId() == file.getStoragePolicyID()) {
        throw new UnsupportedOperationException(
            "Cannot truncate lazy persist file " + src);
      }

      // Check if the file is already being truncated with the same length
      final BlockInfo last = file.getLastBlock();
      if (last != null && last.getBlockUCState()
          == BlockUCState.UNDER_RECOVERY) {
        final BlockInfo truncatedBlock = last.getUnderConstructionFeature()
            .getTruncateBlock();
        if (truncatedBlock != null) {
          final long truncateLength = file.computeFileSize(false, false)
              + truncatedBlock.getNumBytes();
          if (newLength == truncateLength) {
            return new TruncateResult(false, fsd.getAuditFileInfo(iip));
          } else {
            throw new AlreadyBeingCreatedException(
                RecoverLeaseOp.TRUNCATE_FILE.getExceptionMessage(src,
                    clientName, clientMachine, src + " is being truncated."));

View on GitHub (pinned to 2add963021)

Solutions

1. Do not truncate files with the LAZY_PERSIST storage policy; unset the policy or rewrite the file.

When it happens

Trigger: Truncating a file that was created with the LAZY_PERSIST flag.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/98a4db3b0d6d547c. Report an issue: GitHub.