[IMPALA-3524] Spilling joins unnecessarily process spilled partitions with 0 probe rows

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: Impala 2.6.0
• Fix Version/s: Impala 2.9.0
• Component/s: Backend
• Labels: performance ramp-up
• Target Version: Product Backlog
• Assignee: Thomas Tauber-Marshall
• Reporter: Tim Armstrong
• Created: 11/May/16 22:38
• Updated: 18/Aug/17 18:49
• Resolved: 06/Feb/17 20:45

Description

For many join modes, if the spilled partition has no probe rows, we don't need to build the hash table. Currently we always do.

Issue Links

• breaks: IMPALA-5815 Right outer join returns reference to unpinned memory