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https://issues.apache.org/jira/browse/HIVE-20801?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16740788#comment-16740788
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Eugene Koifman commented on HIVE-20801:
---------------------------------------

[~gopalv] what do you mean locks are advisory?  By default, (with Acid on), 
non-transactional tables use standard S/X locks so so assuming things are 
configured properly (and no partial failures), reads should be consistent.  It 
seems that the description of the property is misleading.

Also, if you are disabling all locks for readers, why acquire any locks for 
writers?


> ACID: Allow DbTxnManager to ignore non-ACID table locking
> ---------------------------------------------------------
>
>                 Key: HIVE-20801
>                 URL: https://issues.apache.org/jira/browse/HIVE-20801
>             Project: Hive
>          Issue Type: Bug
>          Components: Locking, Transactions
>    Affects Versions: 4.0.0
>            Reporter: Gopal V
>            Assignee: Gopal V
>            Priority: Major
>              Labels: Branch3Candidate, TODOC
>         Attachments: HIVE-20801.1.patch, HIVE-20801.2.patch, 
> HIVE-20801.2.patch, HIVE-20801.3.patch
>
>
> Enabling ACIDv1 on a cluster produces a central locking bottleneck for all 
> table types, which is not always the intention.
> The Hive locking for non-acid tables are advisory (i.e a client can 
> write/read without locking), which means that the implementation does not 
> offer strong consistency despite the lock manager consuming resources 
> centrally.
> Disabling this lock acquisition would improve the performance of non-ACID 
> tables co-existing with a globally configured DbTxnManager implementation.



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