The low/high watermark settings default to 85%/90% currently. With large disks this might lead to quite a lot of data being unused.
Are there any best practices besides the ones discussed in Minimum disk space needed to account for segment merges in how to configure the watermark settings? Especially how to compute the minimum required free disk space based on the actual (planned) index-sizing?
E.g. in my case I have a few large time-based indices for which segment merging will take place. Also our disaster-recovery procedures might require us to restore indices into newly named ones so we can alias them over the old ones, we likely need to take this into account as well.