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https://issues.apache.org/jira/browse/HAWQ-1624?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16515185#comment-16515185
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Sergei Lebedev edited comment on HAWQ-1624 at 6/17/18 10:31 PM:
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Hmm... looking at the source, the JVM library [seems
to|https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/BlockReaderRemote.java#L243]
read-and-discard on skip. However, I failed to measure this linear-time seek
behaviour in practice.
was (Author: lebedev):
Answering the question above, yes the JVM library [seems
to|https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/BlockReaderRemote.java#L243]
read-and-discard on skip.
> Make libhdfs3 binary compatible with libhdfs
> --------------------------------------------
>
> Key: HAWQ-1624
> URL: https://issues.apache.org/jira/browse/HAWQ-1624
> Project: Apache HAWQ
> Issue Type: Improvement
> Components: libhdfs
> Reporter: Sergei Lebedev
> Assignee: Radar Lei
> Priority: Minor
>
> libhdfs3 is almost binary compatible with libhdfs. The missing bits are:
> * libhdfs3 does not define hdfsPread which nonetheless can be implemented in
> terms of hdfsTell, hdfsSeek and hdfsRead;
> * hdfsSync is called hdfsHSync in libhdfs3;
> * In libhdfs hdfsFlush flushes the internal buffer of the
> BufferedInputStream; in libhdfs3 it always flushes to HDFS, i.e. it does what
> hdfsHFlush should do.
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