Comment 29 for bug 952556

@Steve #27 : Of course the counter for disk spin-ups is "4 Start_Stop_Count" and not "193 Load_Cycle_Count", which is the counter for heads load/park.

I've edited (on my EeePC 1005PE) /etc/hdparm.conf and removed the explicit setting for "apm_battery" which I had previously put, but specified instead "spindown_time = 36" (3 minutes).

I then rebooted my machine, and checked (using "hdparm -I") that I now have « Advanced power management level: 127 » on my HD.

I then left the machine alone for 10 minutes and checked the counters before and after :

4 Start_Stop_Count : No change
193 Load_Cycle_Count: +14

The 2nd one looks reasonable and is not an issue, as the disk can handle much more heads load/unload (typically 600,000 - 800,000) than it can stand start/stops (typically 40,000 - 50,000) - theoretically...

I would assume to get comparable results on my other machines, all of them having more or less the same disk behaviour, however both their brands and models are completely different.

So my advice would be that Ubuntu *may* use a battery default disk apm value of "127", but then *MUST* make sure that the disk gets a default "spindown_time" value which is never less than a couple minutes. My advice would be something between 3 and 5 minutes.

Otherwise we're gonna destroy laptops HDs.