Dojo,
- What table(s) can be truncated in the SLDMADB keyspace in a local cassandra database setup without affecting dataminer operations i.e. impact is limited to only losing historical data?
- If a table is truncated, will the disk space be reclaimed immeditley without performing any further actions like compaction on the database ?
Wale Oguntoyinbo [SLC] [DevOps Enabler] Selected answer as best 9th May 2023
Hi Wale,
- You can truncate the timetrace table, which holds the historical alarm data.
- As per Drop table or truncate table in Cassandra, which is better - Stack Overflow, assuming you are using the truncate command, it will still create snapshots of the data. So you would need to clear the snapshots manually or make use of the auto_snapshot setting in cassandra.yaml (= false). Removing snapshots/preventing them from being saved will free disk space.
Additional : Keeping a DMA from running out of disk space | DataMiner Docs.
Wale Oguntoyinbo [SLC] [DevOps Enabler] Selected answer as best 9th May 2023
You can also truncate infotrace table which holds historical information events.
More info : https://docs.dataminer.services/develop/devguide/Connector/AdvancedDataMinerDataPersistenceNoSqlCassandra.html#infotrace-table.