[ 
https://issues.apache.org/jira/browse/HIVE-12049?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Gopal V updated HIVE-12049:
---------------------------
    Attachment: new-driver-profiles.png

> Provide an option to write serialized thrift objects in final tasks
> -------------------------------------------------------------------
>
>                 Key: HIVE-12049
>                 URL: https://issues.apache.org/jira/browse/HIVE-12049
>             Project: Hive
>          Issue Type: Sub-task
>          Components: HiveServer2
>            Reporter: Rohit Dholakia
>            Assignee: Rohit Dholakia
>         Attachments: HIVE-12049.1.patch, HIVE-12049.11.patch, 
> HIVE-12049.12.patch, HIVE-12049.13.patch, HIVE-12049.14.patch, 
> HIVE-12049.2.patch, HIVE-12049.3.patch, HIVE-12049.4.patch, 
> HIVE-12049.5.patch, HIVE-12049.6.patch, HIVE-12049.7.patch, 
> HIVE-12049.9.patch, new-driver-profiles.png
>
>
> For each fetch request to HiveServer2, we pay the penalty of deserializing 
> the row objects and translating them into a different representation suitable 
> for the RPC transfer. In a moderate to high concurrency scenarios, this can 
> result in significant CPU and memory wastage. By having each task write the 
> appropriate thrift objects to the output files, HiveServer2 can simply stream 
> a batch of rows on the wire without incurring any of the additional cost of 
> deserialization and translation. 
> This can be implemented by writing a new SerDe, which the FileSinkOperator 
> can use to write thrift formatted row batches to the output file. Using the 
> pluggable property of the {{hive.query.result.fileformat}}, we can set it to 
> use SequenceFile and write a batch of thrift formatted rows as a value blob. 
> The FetchTask can now simply read the blob and send it over the wire. On the 
> client side, the *DBC driver can read the blob and since it is already 
> formatted in the way it expects, it can continue building the ResultSet the 
> way it does in the current implementation.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to