Updated the description: I tested with 14.04 and as expected everything goes to sleep when it should and stays sleeping.
I have the serious fear this is a regression in the kernel SATA subsystem. HOWEVER, i'm willing to test it more on 16.04. Could someone point me at a super stripped-down version of 16.04 where one can be absolutely certain there is no userspace daemon waking up the drives? So that it would be possible to isolate the issue being a regression in the kernel or not ** Description changed: On Ubuntu 16.04, if i plug in a USB drive, then unmount it (eject button) in nautilus, then force it to sleep (hdparm -y), the drive reports to be in standby: hdparm -C /dev/sdd /dev/sdd: drive state is: standby However, after some time during which i have not tried to access the drive, the drive seems to spin up again, and reports to be active again: hdparm -C /dev/sdd /dev/sdd: drive state is: active/idle I have been researching on google, askubuntu, irc, but apparently nobody has been able to tell what is that wakes up the drive. Everybody say that if the drive is unmounted, it should stay sleeping. Note: I also tried to add the drive partitions in fstab, so to force gvfs to ignore the drive. Even this failed to keep the drive sleeping. I have not been able to test this on 14.04 yet, but 14.04 successfully keeps internal SATA drives asleep even when mounted unless i explicitly access them. One additional question i would have, at this point, is also whether there is some tool to check what process tries to access the device. Or some sort of tcpdump for SATA.. + + *UPDATE* + I managed to test this on 14.04, and as expected, the disk spins down almost immediately, and stays spun down, and after approximately half hour (maybe less) it goes in standby (disk led blinking regularly: http://gph.is/2yKy20M) + and stays like that. + Also, unlike 16.04, dmesg stays clean without repeating messages about meaningless driver sense errors -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1733068 Title: Unmounted USB drives wake up on 16.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1733068/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
