Cleanur wrote:
AO's job is to fill as much of the SSD as possible, if your pinned SSD volumes are thin and AO is still running against the SSD tier, it will very likely eat up all the space causing your thin volumes to run out of space in that tier.
Actually that is not what HP has told me over and over again, and was confirmed at fairly high level of the product team. AO's code is designed such that it wants to always push data down and that the settings in AO (Performance, Balanced, Cost) only throttle how aggressively AO pushes data down. It will move data up when it meets the criteria, but the way it is coded is designed for the legacy service provider model. We have been urging them to change AO to better utilize higher tiers. Our top 2 tiers are more then 50% empty, yet are NL drives get crushed with IO because AO does not take advantage of empty higher tiers unless the data meets the criteria even if it causes the lower tier to suffer in performance.