sv2000 opened a new pull request #674:
URL: https://github.com/apache/orc/pull/674
… readers and writers
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Current behavior of OrcInput(Output)Format is to create an ORC reader/writer
with the default row batch size of 1024. This may need to be overridden in
certain scenarios to prevent OOMs during reads/writes.
### What changes were proposed in this pull request?
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The changes in this PR expose a new ORC config "orc.row.batch.size", which
can be set as part of the MR job configuration to configure the MR
readers/writers. The configuration is retrieved inside the
ORCInput(Output)Format classes, before the readers/writers are initialized.
### Why are the changes needed?
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The change is needed to provide greater configurability of the ORC MR
readers/writers.
### How was this patch tested?
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The existing unit tests in TestOrcOutputFormat and
TestMapreduceOrcOutputFormat cover the changes to the signature of the
constructors in OrcMapreduceRecordWriter and OrcMapreduceRecordReader. The
change to override the row batch size config was also tested by running a MR
job that used the snapshot version of the orc-mapreduce library.
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