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From "Jitendra Nath Pandey (JIRA)" <>
Subject [jira] [Updated] (HIVE-4160) Vectorized Query Execution in Hive
Date Mon, 18 Mar 2013 23:41:15 GMT


Jitendra Nath Pandey updated HIVE-4160:

    Attachment: Hive-Vectorized-Query-Execution-Design.docx

The attached document covers the outline of the design. Any comments/feedback are welcome.
We will keep updating the document with more details as we include more data types, operators
and expressions. We will also include the vectorized iterator design into the document.
> Vectorized Query Execution in Hive
> ----------------------------------
>                 Key: HIVE-4160
>                 URL:
>             Project: Hive
>          Issue Type: New Feature
>            Reporter: Jitendra Nath Pandey
>            Assignee: Jitendra Nath Pandey
>         Attachments: Hive-Vectorized-Query-Execution-Design.docx
>   Hive query execution engine currently processes one row at a time. A single row of
data goes through all the operators before next row can be processed. This mode of processing
is very inefficient in terms of CPU usage. Research has demonstrated that this yields very
low instructions per cycle [MonetDB]. Also currently hive heavily relies on lazy deserialization
and data columns go through a layer of object inspectors that identify column type, de-serialize
data and determine appropriate expression routines in the inner loop. These layers of virtual
method calls further slow down the processing.

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