[HBASE-16755] Honor flush policy under global memstore pressure

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.4.0, 1.3.1
• Component/s: regionserver

Release Note

Prior to this change, when the memstore low water mark is exceeded on a regionserver, the regionserver will force flush all stores on the regions selected for flushing until we drop below the low water mark. With this change, the regionserver will continue to force flush regions when above the memstore low water mark, but will only flush the stores returned by the configured FlushPolicy.

• Assignee: Ashu Pachauri
• Reporter: Ashu Pachauri
• Created: 04/Oct/16 02:51
• Updated: 01/Jul/22 20:28
• Resolved: 27/Mar/17 19:16

Description

When global memstore reaches the low water mark, we pick the best flushable region and flush all column families for it. This is a suboptimal approach in the sense that it leads to an unnecessarily high file creation rate and IO amplification due to compactions. We should still try to honor the underlying FlushPolicy.

Issue Links

• blocks: HBASE-17524 HBase 1.3.1 release