[HIVE-9729] LLAP: design and implement proper metadata cache

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: llap
• Assignee: Sergey Shelukhin
• Reporter: Sergey Shelukhin
• Created: 19/Feb/15 22:12
• Updated: 17/Feb/16 01:33
• Resolved: 17/Mar/15 17:58

Description

Simple approach: add external priorities to data cache, read metadata parts of orc file into it. Advantage: simple; consistent management (no need to coordinate sizes and eviction between data and metadata caches, etc); disadvantage - have to decode every time.
Maybe add decoded metadata cache on top - fixed size, small and opportunistic? Or some other approach.