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Why can't computers boot instantly? (2013)

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Re: Why can't computers boot instantly? (2013)

#71

Post by adsche »

codeflo wrote: post #46
adsche wrote: post #33

Earlier quoted context omitted.

But then the questions are, why does it need to initialize? Why doesn't it start in an initialized state, what factors make it impossible to determine that initialized state beforehand and storing it? How close can we get?

It's not impossible, just increasingly expensive. Modern software practices tend move a lot of the things that used to be done at compile time to initialization time or runtime. A lot of modern tooling is built around that idea. You gain a lot programmer productivity in exchange for increased memory usage, startup time and battery drain. Is that worth it? The market seems to says yes. As much as people complain about…

Absolutely! But couldn't this be moved from a productivity/time problem to a storage/packaging problem? I.e., do the initialization once and save its state until some major factors change? Storage seems to be quite inexpensive. Emacs does something like this (not saving state after first run but shipping with an initialized state that was generated before, I believe).

Re: Why can't computers boot instantly? (2013)

#72

Post by icebraining »

adsche wrote: post #33
enneff wrote: post #25

Earlier quoted context omitted.

They can. But the more software you need to initialise the slower it is. And modern machines run a lot of software.

But then the questions are, why does it need to initialize? Why doesn't it start in an initialized state, what factors make it impossible to determine that initialized state beforehand and storing it? How close can we get?

I'd say that's essentially what suspend-to-ram means. Booting means throwing that state away and rebuilding it.

Re: Why can't computers boot instantly? (2013)

#73

Post by unnouinceput »

mojuba wrote: post #8

A bigger question for me is, why can't monitors boot instantly? So annoying that a monitor that went to sleep can sometimes take 10-20 seconds longer to wake up than the computer it is attached to.

10 to 20 seconds? What monitor do you have? All decent monitors have a maximum of 5 seconds.

Re: Why can't computers boot instantly? (2013)

#74

Post by adsche »

silon42 wrote: post #40
adsche wrote: post #33

Earlier quoted context omitted.

But then the questions are, why does it need to initialize? Why doesn't it start in an initialized state, what factors make it impossible to determine that initialized state beforehand and storing it? How close can we get?

The fact that reboots happen mostly when software (kernels, system) is upgraded is part of it. It's simplest and most reliable to initialize the system from clean state (I've often had an idea it would be best to reinstall Windows+software for each reboot).

Yes, but do you have an idea why that is, why is it so much more reliable to initalize every time than to generate an initialized configuration and reuse that?

Developer errors? Not enough testing?

Re: Why can't computers boot instantly? (2013)

#75

Post by adsche »

icebraining wrote: post #72
adsche wrote: post #33

Earlier quoted context omitted.

But then the questions are, why does it need to initialize? Why doesn't it start in an initialized state, what factors make it impossible to determine that initialized state beforehand and storing it? How close can we get?

I'd say that's essentially what suspend-to-ram means. Booting means throwing that state away and rebuilding it.

Right, or even just something like suspend-to-disk (or other storage) but for the pre-OS part of the boot (so that constant power isn't required).

Why can this not work?

Re: Why can't computers boot instantly? (2013)

#76

Post by adsche »

Fronzie wrote: post #41
adsche wrote: post #33

Earlier quoted context omitted.

But then the questions are, why does it need to initialize? Why doesn't it start in an initialized state, what factors make it impossible to determine that initialized state beforehand and storing it? How close can we get?

Hardware has lots and lots of pieces of memory, not only block-ram, but also many registers. The needs to be initialized after power-off. As for the software: Hibernate is storing that initialized state.

So would it be impossible/expensive to provide storage for those registers/memory etc. that can survive power-off, and then copy the state from there upon power-on?

How much time would something like that take compared to initialization?

Re: Why can't computers boot instantly? (2013)

#77

Post by dmead »

unnouinceput wrote: post #70
argimenes wrote: post #16

When I was in high school their Amiga would cold boot into a GUI within 3 seconds. It was the same for the Acorn Archimedes in the UK. These computers had the entire GUI OS burnt into the ROM. After that I remember the shock or getting a 386 and waiting minutes for Windows 95 to load. It was like the future had died and was buried by a conspiracy of silence in the industry.

386 and W95? Not a good combination. By the time W95 was out on the market P5 was the latest and greatest and a 486 was the low budget one. You might want to reconsider those memories. As for loading times it all boiled down on how many check-up you wanted or not in your BIOS. As a rule I've always did memory check by BIOS only one time when buying/putting together a new PC and after that I've check it off in BIOS, h…

you're conflating a bunch of stuff here.

Re: Why can't computers boot instantly? (2013)

#78

Post by steve76 »

No, there are risks involved.

In effect, it's making sure it doesn't Dell Laptop shards of "idealized transitor" into your cardiac or central nervous system.

My dear friend. The world cares not for ONE death.

The world cares very much for CANT DIE NO MATTER WHAT.

Invincible Immortality Per Graphene.

... ... ...

R I S E.

Re: Why can't computers boot instantly? (2013)

#79

Post by muthdra »

niklasd wrote: post #36

The link in the answer titled "state machines" is a bit misleading, since it directs to the Wikipedia entry about Finite-state machines. But most computers (the ones we are talking about here) are Turing complete rather than being a (computationally much more limited) finite-state machine.

https://en.wikipedia.org/wiki/State_machine

Re: Why can't computers boot instantly? (2013)

#80

Post by avian »

unnouinceput wrote: post #70
argimenes wrote: post #16

When I was in high school their Amiga would cold boot into a GUI within 3 seconds. It was the same for the Acorn Archimedes in the UK. These computers had the entire GUI OS burnt into the ROM. After that I remember the shock or getting a 386 and waiting minutes for Windows 95 to load. It was like the future had died and was buried by a conspiracy of silence in the industry.

386 and W95? Not a good combination. By the time W95 was out on the market P5 was the latest and greatest and a 486 was the low budget one. You might want to reconsider those memories. As for loading times it all boiled down on how many check-up you wanted or not in your BIOS. As a rule I've always did memory check by BIOS only one time when buying/putting together a new PC and after that I've check it off in BIOS, h…

> By the time W95 was out on the market P5 was the latest and greatest and a 486 was the low budget one. You might want to reconsider those memories.

Maybe the 486 was the low end of what you could buy at the time, but not everyone bought a new computer. My parents upgraded their 386 from Windows 3.1 to 95. It was slow, but usable.

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