Daniel Roudnitsky created HBASE-28559: -----------------------------------------
Summary: Region quotas: Multi-region merge causes inaccurate accounting of region counts Key: HBASE-28559 URL: https://issues.apache.org/jira/browse/HBASE-28559 Project: HBase Issue Type: Bug Components: Quotas Affects Versions: 3.0.0-beta-2 Reporter: Daniel Roudnitsky Assignee: Daniel Roudnitsky There is support for merging more than two regions in one merge procedure with multi-region merge, but if region quotas are enabled, [NamespaceAuditor assumes that every merge is a two region merge|https://github.com/apache/hbase/blob/branch-3/hbase-server/src/main/java/org/apache/hadoop/hbase/namespace/NamespaceAuditor.java#L128-L129]. This causes an inaccurate in memory accounting of region counts in NamespaceStateManager, leading MasterQuotaManager to believe there are more regions than actually exist if multi-region merge is used. To demonstrate the issue: 1. Start with a table with 3 regions in a namespace with a region quota limit of 3 2. Merge all 3 regions leaving 1 region, NamespaceAuditor assumed it was a 2 region merge and believes the number of regions to be 2. 3. Split a region, number of regions is now 2, and NamespaceAuditor believe it to be 3. 4. Attempt another region split, which will fail because NamespaceAuditor believes the ns to be at its region limit of 3 when there are actually only 2 regions. -- This message was sent by Atlassian Jira (v8.20.10#820010)