[jira] [Created] (HBASE-28560) Region quotas: Split/merge procedure rollback can lead to inaccurate account of region counts

["Daniel Roudnitsky (Jira)" <ji...@apache.org>]

Daniel Roudnitsky created HBASE-28560:
-----------------------------------------

             Summary: Region quotas: Split/merge procedure rollback can lead to inaccurate account of region counts
                 Key: HBASE-28560
                 URL: https://issues.apache.org/jira/browse/HBASE-28560
             Project: HBase
          Issue Type: Bug
    Affects Versions: 3.0.0-beta-2
            Reporter: Daniel Roudnitsky
            Assignee: Daniel Roudnitsky


When region quotas are enabled, HMaster keeps an in memory account of region counts through NamespaceStateManager. Region counts in NamespaceStateManager are incremented/decremented at the beginning stages of split/merge procedures, in SPLIT_TABLE_REGION_PRE_OPERATION/MERGE_TABLE_REGIONS_PRE_MERGE_OPERATION before any region is offlined. If the split/merge procedure gets rolled back after the region count change in NamespaceStateManager is made, the split/merge procedure rollback does not revert the region count change in NamespaceStateManager to reflect that the expected split/merge never succeeded. This leaves NamespaceStateManager with an inaccurate account of the number of regions, believing that there are more/less regions than actually exist.  



--
This message was sent by Atlassian Jira
(v8.20.10#820010)