[
https://issues.apache.org/jira/browse/IMPALA-3905?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16559245#comment-16559245
]
ASF subversion and git services commented on IMPALA-3905:
---------------------------------------------------------
Commit 170956b8541a2b159ba711eb1022451f159e3060 in impala's branch
refs/heads/master from [[email protected]]
[ https://git-wip-us.apache.org/repos/asf?p=impala.git;h=170956b ]
IMPALA-7360: sequence scanners sometimes skip blocks
The handling of sync markers after processing a block was broken - eos_
was set if the sync marker straddles the boundary. The expected
behaviour (documented by comments) in this case is that the current
scanner should process the next block, if there is one.
If you look at the logic before the IMPALA-3905 change in commit
931bf49cd90e496df6bf260ae668ec6944f0016c, it split the checking
of eosr() and eof() similar to this patch.
Testing:
Add regression tests that scans a large table with a variety of
different scan range lengths, with some randomisation to exercise
different edge cases. This reliably triggered the bug.
Change-Id: I49a70a4925b0271204b8eea4f980299d7654805a
Reviewed-on: http://gerrit.cloudera.org:8080/11062
Reviewed-by: Michael Ho <[email protected]>
Tested-by: Impala Public Jenkins <[email protected]>
> Single-threaded scan node
> -------------------------
>
> Key: IMPALA-3905
> URL: https://issues.apache.org/jira/browse/IMPALA-3905
> Project: IMPALA
> Issue Type: Sub-task
> Components: Backend
> Affects Versions: Impala 2.6.0
> Reporter: Alexander Behm
> Assignee: Alexander Behm
> Priority: Minor
> Fix For: Impala 2.10.0
>
>
> Since we will multi-thread query execution at the fragment level, we should
> rework our scan nodes and scanners to only use a single thread (the one
> that's executing the fragment).
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
