[HBASE-12451] IncreasingToUpperBoundRegionSplitPolicy may cause unnecessary region splits in rolling update of cluster

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Abandoned
• Assignee: Unassigned
• Reporter: Shaohui Liu
• Created: 10/Nov/14 12:25
• Updated: 17/Jun/22 17:57
• Resolved: 17/Jun/22 17:57

Description

Currently IncreasingToUpperBoundRegionSplitPolicy is the default region split policy. In this policy, split size is the number of regions that are on this server that all are of the same table, cubed, times 2x the region flush size.

But when unloading regions of a regionserver in a cluster using region_mover.rb, the number of regions that are on this server that all are of the same table will decrease, and the split size will decrease too, which may cause the left region split in the regionsever. Region Splits also happens when loading regions of a regionserver in a cluster.

A improvment may set a minimum split size in IncreasingToUpperBoundRegionSplitPolicy
Suggestions are welcomed. Thanks~

Issue Links

• relates to: HBASE-16765 New SteppingRegionSplitPolicy, avoid too aggressive spread of regions for small tables.
• links to: Review at https://reviews.apache.org/r/34467/