[IMPALA-1577] Improve from_utc_timestamp perf which is unpredictable and slow

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Resolved
• Affects Version/s: Impala 2.0
• Component/s: Backend
• Labels: performance
• Target Version: Product Backlog
• Assignee: Unassigned
• Reporter: Skye Wanderman-Milne
• Created: 05/Dec/14 01:16
• Updated: 09/Jul/18 16:45
• Resolved: 09/Jul/18 16:45

Description

The performance of from_utc_timestamp, besides being extremely poor compared to that of other builtin functions such as from_unixtime, depends greatly on the input timezone. Given that evaluating this function can dominate the total query time, it would be good to at least make its performance more consistent, and even better to improve its performance overall.

Issue Links

• is part of: IMPALA-3307 add support for IANA time zone database