Comment 314 for bug 59695

maor:

In fact, I started by monitoring the load/unload parameter using hdparm with Gutsy as well as with Vista. Then I noticed that there was indeed a "click" each time the counter was increased. So at least on my computer, I can tell you when the counter goes up just by listening to the harddrive ( I need to put my ear on the keyboard, but it's easy to notice it).

Ubuntu might be accessing the disk too often, and there is probably room for improvement in the way daemons are working, however I do not believe this is the root cause of the problem. Under Vista the counter is not increased, regardless of the disk activity. So it seems Windows does not park the heads, or maybe only after a very long time. I monitored the load/unload counter on another laptop (IBM T42) running XP. It's the same, the counter is not increased. The only way I found to have the counter going up, is to shake this laptop (IBM's active protection will park the heads when a movement is detected). So Windows, be it XP or Vista has a different behaviour, although the disk's APM parameters are the same. Of course I am only speaking about my laptops. Apparently, jokeman has another experience by comparing ubuntu and XP on his Dell 1400.