Thomas Marshall has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/10503 )

Change subject: IMPALA-6812: Fix flaky Kudu scan tests
......................................................................


Patch Set 1:

So I started playing around with READ_YOUR_WRITES and it doesn't seem to work 
as I would expect, though perhaps I'm doing something wrong:

Suppose I create a new table and scan it without inserting any rows. I get the 
error message 'Snapshot timestamp is earlier than the ancient history mark' 
with the 'Snapshot timestamp' listed in the error message as 0. In this case, 
Impala hasn't called SetLatestObservedTimestamp() since we don't already have a 
timestamp for the session.

Additionally, if I insert rows into the new table, Impala will call 
SetLatestObservedTimestamp() and I can scan it, but if I leave the session idle 
for awhile (>15min with default settings) and then try to scan the table, it 
fails with the 'Snapshot timestamp is earlier than the ancient history mark' 
error.

Note that we never call SetSnapshotMicros()


--
To view, visit http://gerrit.cloudera.org:8080/10503
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I70df84f2cbc663107f2ad029565d3c15bdfbd47c
Gerrit-Change-Number: 10503
Gerrit-PatchSet: 1
Gerrit-Owner: Thomas Marshall <[email protected]>
Gerrit-Reviewer: Dan Hecht <[email protected]>
Gerrit-Reviewer: David Ribeiro Alves <[email protected]>
Gerrit-Reviewer: Thomas Marshall <[email protected]>
Gerrit-Reviewer: Tim Armstrong <[email protected]>
Gerrit-Reviewer: Todd Lipcon <[email protected]>
Gerrit-Comment-Date: Fri, 08 Jun 2018 22:18:36 +0000
Gerrit-HasComments: No

Reply via email to