Hi all, I am an undergraduate currently working on a research project which involves OpenStack Swift. In my project, I have set up Swift to run on 4 disks. I want to put down one of the hard disks to sleep i.e reduce the spin. I am using the hdparm tool in Linux to do this. The problem is that the disk automatically wakes back up after being put to sleep. I have found out that this is due to the fact that all the storage disks of Swift have to be mounted with XFS and the sync processes of XFS require the disk to wake up. I was wondering if there is a way to use a disk without a filesystem in Swift and if not, are there any other ways of putting storage disks in Swift to sleep? I have made sure the object replicator and object auditor do not wake the disk up. My goal is to be able to control putting the disk to sleep and waking it up when I need. Details of set up: Software: OpenStack Swift Newton with Keystone OS: Ubuntu 16.04 Thanks!