EXT4 likes to access disks. Try setting the commit mount option (to 600 or something). I'm not entirely sure what it does though.
Also try running iotop, it's like top or htop, but it shows disk accesses.
]]>hdparm -B 255 /dev/sda
hdparm -y /dev/sda
and right after spinning down, the hdd would immediately spin up again.
So right after that I did
$ find / -amin 2 -ls
find: `/proc/17295/task/17295/fd/5': No such file or directory
find: `/proc/17295/task/17295/fdinfo/5': No such file or directory
find: `/proc/17295/fd/5': No such file or directory
find: `/proc/17295/fdinfo/5': No such file or directory
find: `/proc/17296/task/17296/ns/net': No such file or directory
find: `/proc/17296/task/17296/ns/uts': No such file or directory
find: `/proc/17296/task/17296/ns/ipc': No such file or directory
find: `/proc/17296/ns/net': No such file or directory
find: `/proc/17296/ns/uts': No such file or directory
find: `/proc/17296/ns/ipc': No such file or directory
find: `/run/user/1000/gvfs': Permission denied
so it seems no files have been accessed in the last 2 minutes ie when the spin-up occurred. So why does the drive spin up everytime immediately?
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