[
https://issues.apache.org/jira/browse/HIVE-24468?focusedWorklogId=519667&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-519667
]
ASF GitHub Bot logged work on HIVE-24468:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 03/Dec/20 14:18
Start Date: 03/Dec/20 14:18
Worklog Time Spent: 10m
Work Description: belugabehr commented on pull request #1728:
URL: https://github.com/apache/hive/pull/1728#issuecomment-738021939
@pvary Thanks for the review.
So, the answer is yes. The timestamps could be out of order.
If two instances of HMS are running at the same time, and let's say they
both create events at times T and T+1.
The HMS which generates the event at time T could experience a long GC and
then try to submit it to the DB. At that point, the event at T+1 is going to
be submitted first to the table, and receive a lower ID.
However, there does not seem to be any documentation around this constraint.
1. Is there docs somewhere that state that the event times will always be
increasing from one record to the next?
2. Isn't it a bit confusing that they are assigned an arbitrary time that
masks that true event time (debugging, audit issues)?
3. The time stamps are generated using each HMS's "now" time, which could
possibly not be adequately synced across HMS instances and this issue of
in-order timestamps is in jeopardy. If in-order timestamps are a requirement,
they should be generated using the `now()` of the SQL server itself as a single
source of "now" truth.
Thanks!
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org
Issue Time Tracking
-------------------
Worklog Id: (was: 519667)
Time Spent: 50m (was: 40m)
> Use Event Time instead of Current Time in Notification Log DB Entry
> -------------------------------------------------------------------
>
> Key: HIVE-24468
> URL: https://issues.apache.org/jira/browse/HIVE-24468
> Project: Hive
> Issue Type: Improvement
> Reporter: David Mollitor
> Assignee: David Mollitor
> Priority: Major
> Labels: pull-request-available
> Time Spent: 50m
> Remaining Estimate: 0h
>
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
