Hi All, Looking for some insight into how application data archive and purge is carried out for C* database. Are there standard guidelines on calculating the amount of space that can be used for storing data in a specific node.
Some pointers that I got while researching are; - Allocate 50% space for compaction, e.g. if data size is 50GB then allocate 25GB for compaction. - Snapshot strategy. If old snapshots are present, then they occupy the disk space. - Allocate some percentage of storage ( ???? ) for system tables and OpsCenter tables ? We have a scenario where certain transaction data needs to be archived based on business rules and some purged, so before deciding on an A&P strategy, I am trying to analyze how much transactional data can be stored given the current node capacity. I also found out that the space available metric shown in Opscenter is not very reliable because it doesn’t show the snapshot space. In our case, we have a huge snapshot size. For some unexplained reason, we seem to be taking snapshots of our data every hour and purging them only after 7 days. Thanks, Charu Cisco Systems.
