[
https://issues.apache.org/jira/browse/HIVE-77?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12652195#action_12652195
]
Joydeep Sen Sarma commented on HIVE-77:
---------------------------------------
thx - will fix the inline comments.
static LOG: this is not a blocking issue. I am assuming that log4j itself is
multithread safe. The main issue is that all log events are going to end up in
the same log file - and log entries from different sessions will be interleaved
without any clear headers. There's something called NDC that's apparently used
widely in multi-threaded environments to put prefixes on log entries per thread
(in our case session). we can use NDC interfaces from log4j - but it's more
work - potentially more disruptive changes.
QTestUtil: don't understand this. today every query file is run independently
in a different junit test. if QTestUtil ran all of them (either in sequence or
in parallel) - this would not be possible. can u explain a bit more?
> thread safe query execution
> ---------------------------
>
> Key: HIVE-77
> URL: https://issues.apache.org/jira/browse/HIVE-77
> Project: Hadoop Hive
> Issue Type: Bug
> Components: Server Infrastructure
> Reporter: Joydeep Sen Sarma
> Assignee: Joydeep Sen Sarma
> Attachments: hive-77.patch.1
>
>
> this came up in hive-30 where there's a multithreaded hive server in the
> works. at the minimum, the sessionstate objects should be thread local
> singletons. but filing a more general bug that can cover this issue + code
> audit for any other static variables + test suite for running queries from a
> multi-threaded environment
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
