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https://issues.apache.org/jira/browse/HIVE-23283?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Marton Bod reassigned HIVE-23283:
---------------------------------


> Generate random temp ID for lock enqueue and commitTxn
> ------------------------------------------------------
>
>                 Key: HIVE-23283
>                 URL: https://issues.apache.org/jira/browse/HIVE-23283
>             Project: Hive
>          Issue Type: Improvement
>            Reporter: Marton Bod
>            Assignee: Marton Bod
>            Priority: Major
>
> In order to optimize the S4U scope of enqueue lock and commitTxn, currently a 
> hardcoded constant (-1) is used to first insert all the lock and ws entries 
> with a temporary lockID/commitID. However, in a concurrent environment this 
> seems to cause some performance degradation (and deadlock issues with some 
> rdbms) as multiple concurrent transactions are trying to insert rows with the 
> same primary key (e.g. (-1, 1), (-1, 2), (-1, 3), .. etc. for (extID/intID) 
> in HIVE_LOCKS). The proposed solution is to replace the constant with a 
> random generated negative number, which seems to resolve this issue.



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