[IMPALA-3052] Reorder Parquet Column readers such that slots with probe filters are read first

• Type: Sub-task
• Status: Resolved
• Priority: Minor
• Resolution: Duplicate
• Affects Version/s: Impala 2.5.0
• Component/s: Backend
• Labels: performance runtime-filters
• Target Version: Product Backlog
• Assignee: Unassigned
• Reporter: Mostafa Mokhtar
• Created: 22/Feb/16 02:28
• Updated: 19/Jun/20 15:34
• Resolved: 19/Jun/20 15:34

Description

When applying selective probe filters

HdfsParquetScanner::CreateColumnReaders

should order column_readers such that slots with selective probe filters come first, this should reduce the number of calls to ReadSlot.

Issue Links

• duplicates: IMPALA-2017 Lazy materialization of Parquet columns during query