Re: Sleep vs. Hibernate? ? ?

M.I.5¾ wrote:
"mike" <spamme9@xxxxxxxxx> wrote in message news:lDvJh.5726$rp4.2519@xxxxxxxxxxx
M.I.5¾ wrote:
"mike" <spamme9@xxxxxxxxx> wrote in message news:1UoJh.2752$I56.1848@xxxxxxxxxxx
Val wrote:
Sleep puts it in a low power state, memory content is retained. That's how it wakes up fast. It does continue to draw some power, so it cannot continue in this state indefinetly on battery. If the battery depletes, the system just crashes and you will have to reboot from fresh, losing whatever you had not saved.

Hibernate writes a copy of the current memory content to a reserved space on the hard drive (thus you give up as much hard drive as you have RAM). Then the PC shuts down completely. Upon startup, PC detects it was hibernating and reads the from the hard drive restoring the memory state, as it was when you shut down.

Both methods let you pick up where you left off.

General scheme is to make your power settings put it in standby (sleep) for some period of time, then go to hibernate if you've not used it in that time. Pick the time periods that make sense for your style of working.

Val

"Ray" <rayj.balt@xxxxxxxxxxxxxxxxxxxxx> wrote in message news:oenJh.9054$S06.4967@xxxxxxxxxxx
I have an HP Pavillion which allows me to choose between shut down, hibernate, and sleep.

What's the difference between hibernate and sleep? It wakes up fastest from sleep, so I tend to keep it there.

Is there any downside to Sleep?

I'm curious about the tradeoff for short times.
To hibernate, the machine runs at full speed with the disk spinning for
some period of time. To sleep, there's basically no extra load, but then a constant low draw. At what time interval does the extra power
of hibernating equal the steady drain of sleep?
mike

Hibernate should cause the machine to completely shut down. There should be no more power draw than when the machine is properly turned off.
I'm talking about the part that happens BEFORE the no more power draw...

OK, let me try again with more words.

If I put my laptop to sleep, the power consumption drops to a low value.

A = sleep power multiplied by sleep time.

When I tell it to hibernate, it cranks up to 1.7GHZ, spins the disk a bunch and breathes fire out the cpu fan. Same thing happens when I come
out of hibernation.

B = energy consumed going into and out of hibernation.

For round numbers, assume it takes a minute to hibernate and another minute to come back alive. I submit that the process takes WAY more
energy than to sleep for two minutes.

If I let it sleep forever, it will eventually run the battery flat,
thus exceeding the energy to hibernate.

Given those two extreme points, I submit that the world is mostly
monotonic and there must be a sleep time that consumes energy
equal to the energy used to hibernate.

Therefore, if I intend to be idle less than that time, I should sleep.
Longer than that time, hibernate.

So, the question is, what is that time where the energy consumption
would be equivalent???

At what sleep time does A = B?


I don't really think that the difference is going to severly affect the size of your electric bill.


If my electric bill were the concern, I'd have mentioned it.
It's total useful intermittent operating time on battery that I'm concerned about.
But I do know better than to ask a question on the web.
Chance of a useful answer...well...you know...
.

Relevant Pages

  • Re: Sleep vs. Hibernate? ? ?
    ... It does continue to draw some power, so it cannot continue in this state indefinetly on battery. ... General scheme is to make your power settings put it in standby (sleep) for some period of time, then go to hibernate if you've not used it in that time. ...
    (comp.sys.laptops)
  • Re: Sleep vs. Hibernate? ? ?
    ... Hibernate writes a copy of the current memory content to a reserved ... General scheme is to make your power settings put it in standby (sleep) ... B = energy consumed going into and out of hibernation. ...
    (comp.sys.laptops)
  • Re: Sleep vs. Hibernate? ? ?
    ... It does continue to draw some power, ... Hibernate writes a copy of the current memory content to a reserved space ... General scheme is to make your power settings put it in standby (sleep) ...
    (comp.sys.laptops)
  • Re: Sleep vs. Hibernate? ? ?
    ... If the battery depletes, the system just crashes and you will have to reboot from fresh, losing whatever you had not saved. ... General scheme is to make your power settings put it in standby (sleep) for some period of time, then go to hibernate if you've not used it in that time. ...
    (comp.sys.laptops)
  • Re: Macbook Pro power management seems broken...
    ... intermittent problems seemingly related to the power management ... The setting is "Put the computer to sleep when it is ... goes to sleep when you close the lid. ... on a desk, plugged in, and with a battery, all from a UPS. ...
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