[HBASE-14306] Refine RegionGroupingProvider: fix issues and make it more scalable

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.1.2, 2.0.0
• Fix Version/s: 1.3.0, 2.0.0
• Component/s: wal
• Hadoop Flags: Reviewed

Release Note

In HBASE-14306 we've changed default strategy of RegionGroupingProvider from "identify" to "bounded", so it's required to explicitly set "hbase.wal.regiongrouping.strategy" to "identify" if user still wants to use one WAL per region

Please also notice that in the new framework there will be one WAL per group, and the region-group mapping is decided by RegionGroupingStrategy. Accordingly, we've removed BoundedRegionGroupingProvider and added BoundedRegionGroupingStrategy as a replacement. If you already have a customized class for hbase.wal.regiongrouping.strategy, please check the new logic and make updates if necessary.

• Assignee: Yu Li
• Reporter: Yu Li
• Created: 25/Aug/15 15:48
• Updated: 01/Jul/22 21:05
• Resolved: 14/Sep/15 14:28

Description

There're multiple issues in RegionGroupingProvider, including:

• The provider cache in it is using byte array as the key of ConcurrentHashMap, which is not right (the reason is here)

• It's using IdentityGroupingStrategy to get group and use it as key of the cache, which means the cache will include an entry for each region. This is especially unnecessary when using BoundedRegionGroupingProvider

Besides fixing the above issues, I suggest to change BoundedRegionGroupingProvider from a provider to a pluggable strategy, which will make the whole picture much more clear.

For more details, please refer to the patch

Issue Links

• Is contained by: HBASE-14457 Umbrella: Improve Multiple WAL for production usage
• is related to: HBASE-14448 Refine RegionGroupingProvider Phase-2: remove provider nesting and formalize wal group name