Tim Armstrong created IMPALA-6680:
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Summary: Consider reserving max 2 I/O buffers per Parquet column
when there are multiple columns
Key: IMPALA-6680
URL: https://issues.apache.org/jira/browse/IMPALA-6680
Project: IMPALA
Issue Type: Sub-task
Components: Backend
Affects Versions: Not Applicable
Reporter: Tim Armstrong
Assignee: Tim Armstrong
Reserving 3 * 8MB per column to get triple buffering is minimally useful except
in the case when you're scanning a single very large column. 2 * 8MB is enough
to overlap compute and I/O, and if you have multiple large columns that will
mean that there are multiple I/Os in flight in almost all cases.
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