backup_reports are still repaired using the incremental repair method. This can generate I/O overhead because of the additional anti-compaction phase included necessary for the validation in the incremental repair.
Incremental repair is not the recommended way to repair tables in Cassandra, because subrange repair is more performant and has less impact on the main operations of production clusters.
For historical reasons, the
backup_reports tables have always been configured for incremental repair. This is hardcoded in the Opscenter python files.
It is not possible to change this settings without recompling the code, however it is possible to disable incremental repair for those tables using the incremental repair properties in
In order to disable
backup_reports for incremental repair, the user will have to explicitly set the property
cluster_name.conf file or
opscenterd.conf. By leaving the property blank, no tables will be repaired incrementally and all the tables will be repaired using subrange repair.
One important thing is to unset the
RepairedAt flag in each sstable of the tables
backup_reports by running:
nodetool mark_unrepaired "OpsCenter" backup_reports --force nodetool mark_unrepaired "OpsCenter" settings --force
In this way the tables are marked unrepaired and the subrange repair can start repairing them.
After the changes are effected, proceed to
- restart opscenter
- disable repair service
- enable repair service again.
In order to limit the amount of logging that incremental repair does, even if there are no tables to repair incrementally, users should also include this block in the
[repair_service] section of the
opscenterd.conf as added in the first part of the Procedure above.
# Stop incremental repairs from spamming the event log # Sleep 1 day after each cycle incremental_sleep = 86400
This article is applicable to all 6.x versions of Opscenter. A jira is tracking the request for changing this behaviour in Opscenter: OPSC-15858 - “change repair service property
incremental_repair_tables default to be empty”