[HBASE-23702] `hbase.hstore.flusher.count` setting to 0 breaks HMaster

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha-1, 2.3.0, 2.2.5
• Component/s: regionserver

Environment

HBase-2.2.3

Java openjdk 1.8.0_222

Ubuntu 18.04

• Assignee: Ctest Assign to me
• Reporter: Ctest
• Created: 16/Jan/20 22:43
• Updated: 17/May/20 02:00
• Resolved: 15/May/20 01:40

Description

Summary 

The configuration parameter `hbase.hstore.flusher.count` allows `0` (which turns out to be a bad value after I understand the source code).

When we set `hbase.hstore.flusher.count` to 0, HMaster will fail in 200,000 ms without any error message, but

```
java.lang.RuntimeException: Master not initialized after 200000ms

```

 

There’s no messages pinpointing `hbase.hstore.flusher.count` being the root cause.

 

0 means `MemStoreFlusher` is not alive. During the initialization time of HMaster, `isHealthy()` will be called and it will try to check if `MemStoreFlusher` is alive or not.  However, since we set `hbase.hstore.flusher.count` to 0, there will be no flusher created at the first place, which cause`isHealthy()` to return false. As a consequence, HRegionServer does not enter its main loop.

 

How To Reproduce 

 

The version of HBase: 2.2.3

 

1. Set the value of configuration parameter `hbase.hstore.flusher.count` to `0` in “conf/hbase-site.xml”
2. Start hbase by running “bin/start-hbase.sh”
3. Wait for 3-4 minutes
4. Open the log file “logs/hbase-<username>- master -<pcname>.log”

Issue Links

• links to: GitHub Pull Request #1703
• links to: https://github.com/apache/hbase/pull/1703