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client-tez/src/main/java/org/apache/tez/runtime/library/common/shuffle/orderedgrouped/RssInMemoryMerger.java

@@ -176,6 +176,9 @@ public void merge(List<MapOutput> inputs) throws IOException, InterruptedExcepti
  } else {
  runCombineProcessor(rIter, writer);
  }
+ // The compressed length of writer is calculated when called Writer::close, we must
+ // update the counter after Writer::close. Counter should be updated in normal
+ // execution flow, so do not update counter in finally block.
  writer.close();
  additionalBytesWritten.increment(writer.getCompressedLength());
  writer = null;