Constant data, but increasing memory

Hi all,

apologies if this is a FAQ, but searching for "memory" in the discussions is rather painful. We have a 1.00.101.00.1435831484 Hana. We constantly feed it with new data, do computations and erase old data, so the amount of data remains roughly the same, the tables use about 11G in total (so please do not suggest to merge delta or unload). Unfortunately, the memory usage of the index server is constantly rising about 10G each day, never going down, except when we restart it, then it went from 90G to 20G. Is there a way to stop that, e.g. do some garbage collection? A similar system on SPS8 did not have this problem.

-- Micha