[HBASE-17045] Unify the implementation of small scan and regular scan

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.0
• Fix Version/s: 2.0.0
• Component/s: Client, Scanners
• Hadoop Flags: Reviewed
• Assignee: Duo Zhang
• Reporter: Duo Zhang
• Created: 08/Nov/16 02:25
• Updated: 07/May/19 16:11
• Resolved: 25/Jan/17 01:54

Description

See enis's comment in HBASE-16838

https://issues.apache.org/jira/browse/HBASE-16838?focusedCommentId=15637803&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-15637803

But there is another scenario that we need small scan is that, we do not know the stop row but we only want a small set of results. For example, in the implementation of region locator, we will use small scan and set caching to 1 as we only need one row.

So I think we need to add a new option(maybe called limit?) for the scan object, and deprecate the small option. And the server side modification should also be committed to branch-1 to simplify the logic of async client in 2.0.

Issue Links

• is related to: HBASE-16838 Implement basic scan
• relates to: HBASE-17508 Unify the implementation of small scan and regular scan for sync client
• relates to: HBASE-17489 ClientScanner may send a next request to a RegionScanner which has been exhausted
• links to: reviewboard