[HBASE-6770] Allow scanner setCaching to specify size instead of number of rows

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.89-fb
• Component/s: Client, regionserver
• Assignee: Chen Jin
• Reporter: Karthik Ranganathan
• Created: 13/Sep/12 01:04
• Updated: 14/Jun/22 17:57
• Resolved: 25/Apr/13 18:04

Description

Currently, we have the following api's to customize the behavior of scans:
setCaching() - how many rows to cache on client to speed up scans
setBatch() - max columns per row to return per row to prevent a very large response.

Ideally, we should be able to specify a memory buffer size because:
1. that would take care of both of these use cases.
2. it does not need any knowledge of the size of the rows or cells, as the final thing we are worried about is the available memory.

Issue Links

• relates to: HBASE-2214 Do HBASE-1996 -- setting size to return in scan rather than count of rows -- properly