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https://issues.apache.org/jira/browse/HADOOP-15688?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16588910#comment-16588910
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Sean Mackrory edited comment on HADOOP-15688 at 8/22/18 2:25 PM:
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If anyone's wondering, here's the Parquet code that trips up over this. It gets
FSDataInputStream(FSDataInputStream(InputStream)) so
FSDataInputStream.getWrappedStream() returns another FSDataInputStream which of
course does expose the ByteBufferReadable interface. So it proceeds to set up a
reader that uses ByteBuffer reads and by the time it actually attempts a read
the inner FSDataInputStream checks the inner-most InputStream and sees that it
does NOT implement the ByteBufferReadable interface and throws an
OperationNotSupportedException, at which point Parquet doesn't know what to do
so it just throws the exception up to the top.
https://github.com/apache/parquet-mr/blob/8bfd9b4d8f4fb0a2b522c9328f67eb642066306b/parquet-hadoop/src/main/java/org/apache/parquet/hadoop/util/HadoopStreams.java#L54
I had a bunch of Hive, MR and Spark workloads that failed when using Parquet
and they're all working just fine now. Others with other formats are still
working. I ran the unit tests and it looks like almost all of the failures are
the timeouts I keep seeing from my local machine in the western US (to US West
2). I need to set up a dedicated unit test machine in Azure and see if I can
get better results...
was (Author: mackrorysd):
If anyone's wondering, here's the Parquet code that trips up over this. It gets
FSDataInputStream(FSDataInputStream(InputStream)) so
FSDataInputStream.getWrappedStream() returns another FSDataInputStream which of
course does expose the ByteBufferReadable interface. So it proceeds to set up a
reader that uses ByteBuffer reads and by the time it actually attempts a read
the inner FSDataInputStream checks the inner-most InputStream and sees that it
does NOT implement the ByteBufferReadable interface and throws an
OperationNotSupportedException, at which point Parquet doesn't know what to do
so it just throws the exception up to the top.
https://github.com/apache/parquet-mr/blob/8bfd9b4d8f4fb0a2b522c9328f67eb642066306b/parquet-hadoop/src/main/java/org/apache/parquet/hadoop/util/HadoopStreams.java#L54
> ABFS: InputStream wrapped in FSDataInputStream twice
> ----------------------------------------------------
>
> Key: HADOOP-15688
> URL: https://issues.apache.org/jira/browse/HADOOP-15688
> Project: Hadoop Common
> Issue Type: Sub-task
> Reporter: Sean Mackrory
> Assignee: Sean Mackrory
> Priority: Major
> Attachments: HADOOP-15688.001.patch
>
>
> I can't read Parquet files from ABFS. It has 2 different implementations to
> read seekable streams, and it'll use the one that uses ByteBuffer reads if it
> can. It currently decides to use the ByteBuffer read implementation because
> the FSDataInputStream it gets back wraps another FSDataInputStream, which
> implements ByteBufferReadable.
> That's not the most robust way to check that ByteBufferReads are supported by
> the ultimately underlying InputStream, but it's unnecessary and probably a
> mistake to double-wrap the InputStream, so let's not.
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