Kristen Carlson Accardi <kristen.c.accardi@xxxxxxxxx> writes: [...] > I've updated the hardware based patches and posted to the mailing list - > they do indeed save anywhere from .6-1.5 watts depending on the system, > on my X60 they save about a watt. I don't think that a hardware based > solution is irrelevant at all - it will usually be able to make faster > and more accurrate decisions about when to place the link into lower > power state than software could. Fair enough. But could I point out that the patch I posted from Tejun Heo actually does "stop" the port, not just putting it into low power slumber modes. So, I think it might be able to save more power. Please take a look at it. It is quite sophisticated and could be generalised to more chipsets. Perhaps, on AHCI it can be used in combination with the aggressive link power management. > Note that the previous implementation that was posted didn't work for me, > so I just redid everything. Was that my implementation? I posted it in November last year. It certainly isn't as good as yours http://marc.info/?l=linux-kernel&m=116343039621877&w=2 As you can see, I too thought it saved about 1 W, but Pavel Machek measured 250mW. - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
