[HBASE-18906] Provide Region#waitForFlushes API

• Type: Sub-task
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 2.0.0-alpha-4, 2.0.0
• Component/s: Coprocessors
• Hadoop Flags: Reviewed

Release Note

Provided an API in Region (Exposed to CPs)
boolean waitForFlushes(long timeout)
This call will make the current thread to be waiting for all flushes in this region to be finished. (Upto the time out time being specified). The boolean return value specify whether the flushes are really over or the time out being elapsed. Return false when timeout elapsed but flushes are not over or true when flushes are over

• Assignee: Anoop Sam John
• Reporter: Anoop Sam John
• Created: 29/Sep/17 03:48
• Updated: 17/Jun/22 05:22
• Resolved: 27/Oct/17 06:27

Description

Expose an API for the CPs to wait for all on going flushes in a Region. The API should support taking a time out.

Background
While reviewing HBASE-18183, Andy pointed out that Phoenix uses waitForFlushesAndCompactions and/or waitForFlushes for diff reasons. This issue is to see why they need them and whether alternate ways are possible. This seems to be too much internal stuff and a normal CP hook calling these would be dangerous.
If there are alternate ways for Phoenix not to use this and not landing in issues (As said by Andy) we should suggest/fix for them.

Issue Links

• is related to: HBASE-18905 Allow CPs to request flush on Region and know the completion of the requested flush
• relates to: HBASE-18989 Polish the compaction related CP hooks