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https://issues.apache.org/jira/browse/HADOOP-15598?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Prasanth Jayachandran updated HADOOP-15598:
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    Description: When profiling a multi-threaded hive streaming ingest, 
observed lock contention on java.util.Properties getProperty() to check if 
os.arch is "sparc". java.util.Properties internally uses HashTable. 
HashTable.get() is synchronized method. In the test application, on a 30s 
profile with 64 threads ~40% CPU time is spent on getProperty() contention. See 
attached snapshot.  (was: When profiling a multi-threaded hive streaming 
ingest, observed lock contention on java.util.Properties getProperty() to check 
if os is "sparc". java.util.Properties internally uses HashTable. 
HashTable.get() is synchronized method. In the test application, on a 30s 
profile with 64 threads ~40% CPU time is spent on getProperty() contention. See 
attached snapshot.)

> DataChecksum calculate checksum is contented on hashtable synchronization
> -------------------------------------------------------------------------
>
>                 Key: HADOOP-15598
>                 URL: https://issues.apache.org/jira/browse/HADOOP-15598
>             Project: Hadoop Common
>          Issue Type: Improvement
>          Components: common
>    Affects Versions: 3.2.0, 3.1.1
>            Reporter: Prasanth Jayachandran
>            Assignee: Prasanth Jayachandran
>            Priority: Major
>         Attachments: HADOOP-15598.1.patch, HADOOP-15598.1.patch, Screen Shot 
> 2018-07-11 at 1.45.06 AM.png, Screen Shot 2018-07-11 at 2.01.54 AM.png
>
>
> When profiling a multi-threaded hive streaming ingest, observed lock 
> contention on java.util.Properties getProperty() to check if os.arch is 
> "sparc". java.util.Properties internally uses HashTable. HashTable.get() is 
> synchronized method. In the test application, on a 30s profile with 64 
> threads ~40% CPU time is spent on getProperty() contention. See attached 
> snapshot.



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