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https://issues.apache.org/jira/browse/PARQUET-1911?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17653512#comment-17653512
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Anthony Pessy commented on PARQUET-1911:
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[[email protected]] Sorry for the late reply it seems I did not receive a
notification.
The truncation on min/max is not sufficient because I'm having an out of memory
way before I'm even close to writing a footer as the truncation takes place
when it actually write the footer (If I recall) and it still keep the whole
values in memory until then.
(The whole idea of min/max against a HTML payload or similar fields does not
have much sense anyway).
I'll try to see if I can gather the time to suggest a PR as I'd like to stop
relying on a forked version.
> Add way to disables statistics on a per column basis
> ----------------------------------------------------
>
> Key: PARQUET-1911
> URL: https://issues.apache.org/jira/browse/PARQUET-1911
> Project: Parquet
> Issue Type: New Feature
> Components: parquet-mr
> Reporter: Anthony Pessy
> Priority: Major
> Attachments: NoOpStatistics.java,
> add_config_to_opt-out_of_a_column's_statistics.patch
>
>
> When you write dataset with BINARY columns that can be fairly large (several
> Mbs) you can often end with an OutOfMemory error where you either have to:
>
> - Throw more RAM
> - Increase number of output files
> - Play with Block size
>
> Using a fork with increased checks frequency for row group size help but it
> is not enough. (PR: [https://github.com/apache/parquet-mr/pull/470])
>
>
> The OutOfMemory error is now caused due to the accumulation of min/max values
> for those columns for each BlockMetaData.
>
> The "parquet.statistics.truncate.length" configuration is of no help because
> it is applied during the footer serialization whereas the OOM occurs before
> that.
>
> I think it would be nice to have, like for dictionary or bloom filter, a way
> to disable the statistic on a per-column basis.
>
> Could be very useful to lower memory consumption when stats of huge binary
> column are unnecessary.
>
>
>
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