Will-Lo opened a new pull request, #3762:
URL: https://github.com/apache/gobblin/pull/3762

   Dear Gobblin maintainers,
   
   Please accept this PR. I understand that it will not be reviewed until I 
have checked off all the steps below!
   
   
   ### JIRA
   - [ ] My PR addresses the following [Gobblin 
JIRA](https://issues.apache.org/jira/browse/GOBBLIN/) issues and references 
them in the PR title. For example, "[GOBBLIN-XXX] My Gobblin PR"
       - https://issues.apache.org/jira/browse/GOBBLIN-1898
   
   
   ### Description
   - [ ] Here are some details about my PR, including screenshots (if 
applicable):
   
   The ORCWriter's new self tuning feature leads to slower write frequency when 
it comes to ingesting datasets with a low volume of records.
   
   This is primarily caused by the assumption that the native ORC writer will 
be saturated, which leads to the memory footprint of STRIPE_SIZE + 
avgSizeOfRecord*rowsBetweenMemoryCheck.
   
   However, this is generally not the case when there are only a few records to 
write due to a low volume dataset, and causes slow writes. We should utilize a 
newer API on ORCWriter brought in by https://github.com/apache/orc/pull/1057
   
   Some other improvements so that memory consumption by the writer is 
fluctuates less:
   1. Persist more state in between writers so that writers will start at a 
more reasonable base point based off the past
   2. When increasing batchSize, raise it by a percentage of the error 
(proportional control) so that batchsize leads to less overshoot in memory usage
   3. Reveal more configuration knobs to manually tune the limits of the self 
tuning writer
   
   
   ### Tests
   - [ ] My PR adds the following unit tests __OR__ does not need testing for 
this extremely good reason:
   
   ### Commits
   - [ ] My commits all reference JIRA issues in their subject lines, and I 
have squashed multiple commits if they address the same issue. In addition, my 
commits follow the guidelines from "[How to write a good git commit 
message](http://chris.beams.io/posts/git-commit/)":
       1. Subject is separated from body by a blank line
       2. Subject is limited to 50 characters
       5. Subject does not end with a period
       6. Subject uses the imperative mood ("add", not "adding")
       7. Body wraps at 72 characters
       8. Body explains "what" and "why", not "how"
   
   


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