[ASTERIXDB-1945] Fix BufferCache API/Lifecycle

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Component/s: STO - Storage
• Assignee: Abdullah Alamoudi
• Reporter: Abdullah Alamoudi
• Created: 18/Jun/17 07:52
• Updated: 21/Jun/17 15:25
• Resolved: 21/Jun/17 15:25

Description

Currently, BufferCache has an interesting behavior such as:
1. CreateFile doesn't create a file but only create a name-id mapping in memory.
2. To get the id of a file, the caller must have access to the map associated with the buffer cache.
3. openFile. If create file was called before openFile, then it creates the file. If the file already exists, it deletes it and create a new file.

This should be fixed and given clear behavior that matches the expected API. All usages of the buffer cache must be fixed as well.