Hi, Well,
> Yes, when I'm running in AC, Load_Cycle_Count don't increase in my laptop. > Messias, and in your laptop? > Yes, when I'm running in AC, Load_Cycle_Count don't increase in my laptop and and increase very. > And... Messias can hear this sound when Load_Cycle_Count increase: > <http://bugzilla.kernel.org/attachment.cgi?id=8777&action=view> > Yes, I hear a sound almost identical to that. -- []'s Messias Alves GUD-BR-PI 2009/2/18 Bart Samwel <b...@samwel.tk> > Renato S. Yamane wrote: > > Bart Samwel wrote: > >> Note that that should be 254. 255 gives undefined behaviour for lots of > >> hardware. > > > > 254 don't fix the problem (Load_Cycle_Count still increasing). > > Even if you do it and do nothing else, so that nothing runs laptop mode > tools and/or acpi-support? > > > And check below: > > > > # hdparm -B 254 /dev/sda > > /dev/sda: > > setting Advanced Power Management level to 0xfe (254) > > > > # hdparm -B 255 /dev/sda > > /dev/sda: > > setting Advanced Power Management level to disabled > > > > So, I really think that correct is 255. What you think? > > Nope, 254 is correct for this. 255 means "do what you want", 254 means "do > as little power management as possible". For many drives "disable power > management" does the same as 128 (the default). > > >> Here's a question to everybody here: does the load cycle count increase > >> quickly *while you're on AC*? > > > > - When I run in AC, Load_Cycle_Count never increase. > > - When I run in battery, Load_Cycle_Count increase at least 1 time per > minute. No more than 2 times per minute. > > Ah, it works exactly as designed then! > > >> The theory is that nobody works on battery 24 hrs/day, and that HD > >> power management actually has benefits while working on battery. > >> We've calculated that with this solution, even with very mobile usage > >> patterns your drive should live for years. If the load cycle count > >> increases while you're on AC, then the solution is broken. > > > > Yes, when I'm running in AC, Load_Cycle_Count don't increase in my > laptop. > > Messias, and in your laptop? > > > > And... Messias can hear this sound when Load_Cycle_Count increase: > > <http://bugzilla.kernel.org/attachment.cgi?id=8777&action=view> > > > > This can be a different bug? > > I don't have sound so I can't see if this is the same. On my laptop it > gives a pretty loud click. This is expected, this is just the sound of the > head parking. > > >> If the load cycle count > >> increases only on battery, then it works as designed.) > > > > You think that is a good idea change "hdparm -B" from 254 to 255 in my > case (/etc/acpi/battery.d/90-hdparm.sh)? > > > > Because when I run as 254, I get: > > setting Advanced Power Management level to 0xfe (254) > > > > And when I run as 255, I get: > > setting Advanced Power Management level to disabled > > No, I'd keep it at 254 if it works for you. And I wouldn't worry if the > load cycle count increases while you're on battery: you're not on battery > all day. > > Here's the math again, which shows why this is safe: > > 8 hours on battery per day * 60 minutes per hour * 1 load cycle per minute > = 480 cycles per day. > > Drives are rated for 600000 load cycles -> 600000 / 480 = 1250 days = 3.42 > years. > > And that's if you use your laptop on battery for 8 hours EVERY DAY for 3.42 > years. Nobody does that: a typical Li-Ion battery can take 300 load cycles > before it's exhausted and needs to be replaced. So, assuming you have a > battery which can handle 8 hours (!) you'd need to be in your 5th > replacement battery before your hard drive fails. Do you know ANYONE who > uses a laptop into its second replacement battery? I don't either. So this > is perfectly safe. :-) > > Cheers, > Bart > >
