private static boolean shouldReadDeleteDeltasWithLlap(Configuration conf, boolean metaDataLevelSufficient) {
    String ddCacheLevel = HiveConf.getVar(conf, ConfVars.LLAP_IO_CACHE_DELETEDELTAS);
    return ("all".equals(ddCacheLevel) || (metaDataLevelSufficient && ddCacheLevel.equals("metadata")))
        && LlapHiveUtils.isLlapMode(conf) && LlapProxy.isDaemon() && LlapProxy.getIo() != null;
  }
Checks whether delete delta files should be read through LLAP IO by verifying that:
- delete delta caching feature is turned on in configuration
- this execution is inside an LLAP daemon, and LLAP IO is enabled
@param conf job conf / session conf
@param metaDataLevelSufficient if true: 'metadata' level delete delta caching is sufficient to return true
                               if false: full delete delta caching ('all') is required for this to return true
@return
ql/src/java/org/apache/hadoop/hive/ql/io/orc/VectorizedOrcAcidRowBatchReader.java