While using Apache Geode/Gemfire implementation, my requirement is to not only have the IMDG functionality but also I want to commit the values to disk-stores. In case, all of my Geode server go down, I would like to to bring them back and have a persistence key-values.
Now, when i remove a key from the cache, the key and value is removed from all the clustered cache (or say I use destroy mode for eviction action). However, the disk space is not reclaimed or reduced; so, if I continue to use persistence_overflow for regions, how should I clear up the disk space as well to accommodate new entries?
Again, i understand there is compact option, but then, i am not looking for compaction, i want to completely remove the key/value pair and reclaim the disk space?
As far as I know, this is not configurable under the current implementation: each GemFire/Geode member configured with a disk-store creates the oplog file occupying whatever was configured through the max-oplog-size property, which defaults to 1GB. During regular execution, obsolete operations are only removed from the oplogs during compaction, as explained in Design Your Disk Stores.
Hope this helps, cheers.