Butao Zhang

@abstractdog Can we upgrade hadoop to 3.3.4? I have tested hive maser with hadoop3.3.4(https://github.com/apache/hive/pull/3578) , and if i change tez's hadoop dependency to 3.3.4, everything looks ok.

Great! If this PR is merged into Tez 0.10.2, then we can continue to upgrade hadoop version in hive repo.

> the build will pass, I tried till 3.3.3 when trying to upgrade, hive doesn't pose any issues there, but Tez doesn't work with Hive in actual cluster that is...

 Tested this Pr with Hadoop3.3.4 & Tez0.10.2, and HS2 started failed with above WARN. This is because Tez0.10.2 added related hadoop3.3.1 jars(e.g. `hadoop-hdfs-client-3.3.1.jar`) to binary package and this caused...

Gentle ping @nrg4878 @saihemanth-cloudera

@nrg4878 @dengzhhu653 Could you please take a look? thx

> please resolve all the comments that have been addressed. @nrg4878 Done

> Waiting till all inputs are ready is intensional and having this to timeout based approach could destabilize and cause corner case issues. @rbalamohan I agree. That's why the timeout...

cc @saihemanth-cloudera @nrg4878

> Can we a have a test (either unit test or qtest) for this? with a dummy keys and printing it somewhere @shameersss1 Thx for your advice. This PR seems...