Im so sorry, but „zero page reclaim“ receive no consideration by me. One of the reasons are that i not relay know what it is. The second thing is that we run a long time only with solaris (RIP SUN). After a course for the brand new HDS VSP G1000 i get some infos about that – and i try it. In the meantime we got a LOT of X86 (ESX) datastores. It need a lot of time, but startetd out of the Hitachi Command Suite after ~24hours on one machine i save 6tb of space. Thats not SO much in 200TB cabinets, but this are 6TB….and i got a lot more of machines.