[HBASE-9769] Improve performance of a Scanner with explicit column list when rows are small/medium size - ASF JIRA

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Release Note:

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The feature allows to improve performance of scan operations when table rows are small/medium size and scan operation contains explicit set of column:qualifiers to filter on. By default, the feature is disabled. To enable it set Scan.HINT_NARROW_ROWS attribute of Scan object instance:
Scan scan = ...
scan.setAttribute(Scan.HINT_NARROW_ROWS, Bytes.toBytes(Boolean.TRUE));

The performance improvement depends on a average row size. The smaller rows are - the larger performance improvement is.

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The feature allows to improve performance of scan operations when table rows are small/medium size and scan operation contains explicit set of column:qualifiers to filter on. By default, the feature is disabled. To enable it set Scan.HINT_NARROW_ROWS attribute of Scan object instance: Scan scan = ... scan.setAttribute(Scan.HINT_NARROW_ROWS, Bytes.toBytes(Boolean.TRUE)); The performance improvement depends on a average row size. The smaller rows are - the larger performance improvement is.

relates to

HBASE-13109 Make better SEEK vs SKIP decisions during scanning