Alexander Koch

Unfortunately I've only got one machine left that has rotating disks (migrated anything else to NVMe SSDs) and that one is running `linux-lts` which is currently at 5.4.21 on Arch....

I've tried with a recent Arch installation on Kernel `5.5.6.arch1-1`. No issues so far, disk getting put to sleep as expected. @nick-s-b could you please install the version from branch...

Looking at your traces I see that the read counter (first number) is constantly increased. That's why the disk is not put to sleep. Interestingly, in your last trace this...

I'm happy to accept pull requests for ignoring the read counter, if SMART readouts really make that one constantly increase. However I must admit I don't have any rotating disks...

Looking at the [Kernel documentation](https://www.kernel.org/doc/Documentation/block/stat.txt) for `/sys/block//stat` I see that, apart from I/O counters there is also sector counters: ``` Name units description ---- ----- ----------- read I/Os requests number...

@rankaiyx Thanks for 5 notification mails within two hours ;) I'm not sure I can follow your explanations, specifically the latest one with the flag. Either way, this is something...

Great news @bocki! I'll happily give your PR another pair of eyes and merge when looking good.