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https://issues.apache.org/jira/browse/ARROW-7224?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17298178#comment-17298178
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Ben Kietzman commented on ARROW-7224:
-------------------------------------

bq.  I have a use case that involves a dataset with over 1M files on s3. I 
update the cache file incrementally after an overnight update job completes 
avoiding having to reindex the entire dataset each time.

Another potential workaround would be to create a custom FileSystem which 
replaces directory listing calls with reads of this cache file. In Python, this 
can be done by subclassing PyFileSystem and 
[FileSystemHandler|https://arrow.apache.org/docs/python/generated/pyarrow.fs.FileSystemHandler.html#pyarrow.fs.FileSystemHandler]
 or through 
[fsspec|https://arrow.apache.org/docs/python/filesystems.html#using-fsspec-compatible-filesystems]

> [C++][Dataset] Partition level filters should be able to provide filtering to 
> file systems
> ------------------------------------------------------------------------------------------
>
>                 Key: ARROW-7224
>                 URL: https://issues.apache.org/jira/browse/ARROW-7224
>             Project: Apache Arrow
>          Issue Type: Improvement
>          Components: C++
>            Reporter: Micah Kornfield
>            Priority: Major
>              Labels: dataset
>
> When providing a filter for partitions, it should be possible in some cases 
> to use it to optimize file system list calls.  This can greatly improve the 
> speed for reading data from partitions because fewer number of 
> directories/files need to be explored/expanded.  I've fallen behind on the 
> dataset code, but I want to make sure this issue is tracked someplace.  This 
> came up in SO question linked below (feel free to correct my analysis if I 
> missed the functionality someplace).
> Reference: 
> [https://stackoverflow.com/questions/58868584/pyarrow-parquetdataset-read-is-slow-on-a-hive-partitioned-s3-dataset-despite-u/58951477#58951477]



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