On Fri, 11 Jan 2013 13:43:27 +0900 Minchan Kim <minchan@xxxxxxxxxx> wrote: > Hi Andrew, > > On Thu, Jan 10, 2013 at 01:58:28PM -0800, Andrew Morton wrote: > > On Thu, 10 Jan 2013 11:23:06 +0900 > > Minchan Kim <minchan@xxxxxxxxxx> wrote: > > > > > > I have a feeling that laptop mode has bitrotted and these patches are > > > > kinda hacking around as-yet-not-understood failures... > > > > > > Absolutely, this patch is last guard for unexpectable behavior. > > > As I mentioned in cover-letter, Luigi's problem could be solved either [1/2] > > > or [2/2] but I wanted to add this as last resort in case of unexpected > > > emergency. But you're right. It's not good to hide the problem like this path > > > so let's drop [2/2]. > > > > > > Also, I absolutely agree it has bitrotted so for correcting it, we need a > > > volunteer who have to inverstigate power saveing experiment with long time. > > > So [1/2] would be band-aid until that. > > > > I'm inclined to hold off on 1/2 as well, really. > > Then, what's your plan? My plan is to sit here until someone gets down and fully tests and fixes laptop-mode. Making it work properly, reliably and as-designed. Or perhaps someone wants to make the case that we just don't need it any more (SSDs are silent!) and removes it all. > > > > The point of laptop_mode isn't to save power btw - it is to minimise > > the frequency with which the disk drive is spun up. By deferring and > > then batching writeout operations, basically. > > I don't get it. Why should we minimise such frequency? Because my laptop was going clickety every minute and was keeping me awake. > It's for saving the power to increase batter life. It might well have that effect, dunno. That wasn't my intent. Testing needed! > As I real all document about laptop_mode, they all said about the power > or battery life saving. > > 1. Documentation/laptops/laptop-mode.txt > 2. http://linux.die.net/man/8/laptop_mode > 3. http://samwel.tk/laptop_mode/ > 3. http://www.thinkwiki.org/wiki/Laptop-mode Documentation creep ;) Ten years ago, gad: http://lwn.net/Articles/1652/ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>