You have the raw data and the tsidx files that make up an index. Those tsidx files utilize quite a bit of storage (size is based on uniqueness of data). So you could always set tsidx reduction based on index which should give you ~30-50% reduction in disk space. But be warned, this will have a significant performance hit and should only be used on data that is rarely searched but must be retained
add a cap to indexes size in indexes.conf
leverage the config:
maxTotalDataSizeMB = <nonnegative integer>
* The maximum size of an index (in MB).
* If an index grows larger than the maximum size, the oldest data is frozen.
* This parameter only applies to hot, warm, and cold buckets. It does not
apply to thawed buckets.
* Highest legal value is 4294967295
* Defaults to 500000.
read here more:
also read this manual all the way through for capacity planing:
hope it helps