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https://issues.apache.org/jira/browse/AVRO-1208?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13569222#comment-13569222
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Yin Huai commented on AVRO-1208:
--------------------------------

Also, in the test mentioned above, using startBlockWithPrefetch to only read 1 
block (<num of prefetched blocks>=0) make the throughput drops from ~70 MiB/s 
(original Trevni) to ~66 MiB/s.
                
> Improve Trevni's performance on row-oriented data access
> --------------------------------------------------------
>
>                 Key: AVRO-1208
>                 URL: https://issues.apache.org/jira/browse/AVRO-1208
>             Project: Avro
>          Issue Type: Improvement
>    Affects Versions: 1.7.3
>            Reporter: Yin Huai
>            Assignee: Yin Huai
>         Attachments: AVRO-1208.1.patch
>
>
> Trevni uses an 64KB internal buffer to store values of a column. When 
> accessing a column, it reads 64KB (if we do not consider compression and 
> checksum) data from the storage layer. However, when the table is accessed in 
> a row-oriented fashion (a entire row needs to be handed over to the upper 
> layer), in the worst case (a full table scan and values of this table are all 
> the same size), every 64KB data read can cause a seek.
> This jira is used to discuss if we should consider the data access pattern 
> mentioned above and if so, how to improve the performance of Trevni. 
> Row-oriented data processing engines, e.g. Hive, can benefit from this work.

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