[IDEA] Poor man's UPS

[IDEA] Poor man's UPS

[Pau Garcia i Quiles]

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Hello,

This is an idea a had some time ago. It might be a waste of time or it might 
be a good idea, you decide.

A short description would be "continuous system hibernation". Say you are 
running Firefox, writing an e-mail in mutt and compiling the next X.org 
release. The power goes off, your computer crashes or something happens and 
you lose everything you were doing (yes, sadly you haved saved your e-mail as 
a draft yet).

The "continuous hibernation" is some kind of memory snapshots taken, say, 
every 5 minutes. The next time your system starts after a crash, it'd say "oh 
oh, looks like something went wrong" and offer you a list of the last N (for 
instance, 4) snapshots and you can recover your system to the very same state 
it was before power went off or your dog unplugged your CPU. It might even 
ask you which individual applications you want to start from that snapshot:  
maybe you don't want to start Quake 3.

Provided the implementation is fast enough and you have a large hard drive, it 
might even allow you to say: "I want to restore the system to the same stage 
it had on Monday, 11.04PM"

That's it. Please, shoot at the idea not at the idealist :-)

- -- 
Pau Garcia i Quiles
http://www.elpauer.org
(Due to the amount of work, I usually need 10 days to answer)
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Re: [IDEA] Poor man's UPS

[Dave Jones]

On Sun, May 21, 2006 at 09:31:30PM +0200, Pau Garcia i Quiles wrote:

 > A short description would be "continuous system hibernation". Say you are 
 > running Firefox, writing an e-mail in mutt and compiling the next X.org 
 > release. The power goes off, your computer crashes or something happens and 
 > you lose everything you were doing (yes, sadly you haved saved your e-mail as 
 > a draft yet).
 > 
 > The "continuous hibernation" is some kind of memory snapshots taken, say, 
 > every 5 minutes. The next time your system starts after a crash, it'd say "oh 
 > oh, looks like something went wrong" and offer you a list of the last N (for 
 > instance, 4) snapshots and you can recover your system to the very same state 
 > it was before power went off or your dog unplugged your CPU. It might even 
 > ask you which individual applications you want to start from that snapshot:  
 > maybe you don't want to start Quake 3.
 > 
 > Provided the implementation is fast enough and you have a large hard drive, it 
 > might even allow you to say: "I want to restore the system to the same stage 
 > it had on Monday, 11.04PM"
 > 
 > That's it. Please, shoot at the idea not at the idealist :-)

One problem is that the on-disk state may not match the state
of the running programs on resume, which could lead to all sorts
of bad things happening.

		Dave


-- 
http://www.codemonkey.org.uk

Re: [IDEA] Poor man's UPS

[Michael Buesch]

>  > The "continuous hibernation" is some kind of memory snapshots taken, say, 
>  > every 5 minutes. The next time your system starts after a crash, it'd say "oh 

You really want a system, which freezes for 10-20 seconds every 5 minutes,
and thaws again when the image is written?

Re: [IDEA] Poor man's UPS

[Avi Kivity]

Michael Buesch wrote:
>>  > The "continuous hibernation" is some kind of memory snapshots taken, say, 
>>  > every 5 minutes. The next time your system starts after a crash, it'd say "oh 
>>     
>
> You really want a system, which freezes for 10-20 seconds every 5 minutes,
> and thaws again when the image is written?
>   

The snapshot could be taken in the background, by marking all pages 
read-only, starting a thread to write them to disk, and continuing 
normal processing.

Such systems have been implemented in the past, see for example 
http://www.eros-os.org/.

-- 
error compiling committee.c: too many arguments to function

Re: [IDEA] Poor man's UPS

[Jan Engelhardt]

>> You really want a system, which freezes for 10-20 seconds every 5 minutes,
>> and thaws again when the image is written?
>
> The snapshot could be taken in the background, by marking all pages read-only,
> starting a thread to write them to disk, and continuing normal processing.
>
> Such systems have been implemented in the past, see for example
> http://www.eros-os.org/.
>

Another one is VMware's background snapshot feature. Granted, it writes
"quite much" (IMO) to disk, but it's better than a foreground snapshot. :)


Jan Engelhardt
-- 

Re: [IDEA] Poor man's UPS

[Christian Trefzer]

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Hi there,

On Sun, May 21, 2006 at 09:31:30PM +0200, Pau Garcia i Quiles wrote:

> [interesting idea with complex implementational problems]

I think it would be cheaper ("costs" for your solutin in terms of
required I/O power and hard disk space) to use two or more lead
batteries which are charged and discharged in a round-robin fashion,
controlled by some smart home-brew circuitry, and connect the beast to
some control/monitoring software via RS-232 ; )

The logic should at least completely drain the battery before
recharging, and maybe even do a quick-and-hot charge-discharge-charge
cycle every now and then to reduce chemical byproducts at the cathode -
or was it the anode? Well, one of them is dissolved over time, and the
other one collects some sulfate or sulfide or something. If you want it
really complicated and robust, you might want to monitor the electric
parameters of the batteries at all times, to estimate the minimum
remaining time once the power is cut. You'd then have to shut down, or
better hibernate, the system cleanly within that time frame to be safe
from data loss.

I'd love to do something like that sort of in-between the PSU for a
single machine, for this would avoid the need to go from AC to DC and
back, but lacking the electrotechnical skills I'm not self-confident
enough to try and waste my PSU. Anyway, this has gone way off-topic by
now.

Kind regards,
Chris

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Re: [IDEA] Poor man's UPS

[Jan Knutar]

On Monday 22 May 2006 01:40, Christian Trefzer wrote:
>
> I think it would be cheaper ("costs" for your solutin in terms of
> required I/O power and hard disk space) to use two or more lead
> batteries which are charged and discharged in a round-robin fashion,
> controlled by some smart home-brew circuitry, and connect the beast to
> some control/monitoring software via RS-232 ; )
> 
> The logic should at least completely drain the battery before
> recharging,

I thought deep discharge cycles were unhealthy for lead batteries?

Re: [IDEA] Poor man's UPS

[linux-os (Dick Johnson)]

On Mon, 22 May 2006, Jan Knutar wrote:

> On Monday 22 May 2006 01:40, Christian Trefzer wrote:
>>
>> I think it would be cheaper ("costs" for your solutin in terms of
>> required I/O power and hard disk space) to use two or more lead
>> batteries which are charged and discharged in a round-robin fashion,
>> controlled by some smart home-brew circuitry, and connect the beast to
>> some control/monitoring software via RS-232 ; )
>>
>> The logic should at least completely drain the battery before
>> recharging,
>
> I thought deep discharge cycles were unhealthy for lead batteries?

Yes. It's some of the more modern chemistries that need deep discharges
because they tend to "remember". Lead acid batteries, both wet cells
and gel cells should be taken down to about 66 percent capacity and
that's 66 percent capacity, not some arbitrary voltage. For instance,
a 24 ampere-hour battery, fully charged at 25 degC, has a terminal
voltage of 13.2 volts after the load is applied. Presumably it
contains 13.2 * 24 * 3600 = 1,140,480 joules (watt-seconds) of
energy. You get to use 66 percent of this, i.e., 752,717 joules
before it needs charging. You can't detect the charge state by
looking at the terminal voltage! You need to actually measure
the voltage and current during charge and discharge to maintain
battery health. Otherwise, you just throw them away every year or
so. The telephone company has lead-acid batteries that have been
running for 50 years and they will be good "forever" because they
carefully (automatically) maintain them.

NICAD batteries used in aircraft will wear out in a short time
no matter what you do with them. They are used only because they
have a high power density (are lighter than lead acid). They will
"remember" shallow discharge cycles and fail unless they are
subjected to deep discharge cycles. If they are discharged too
deeply, they will fail to charge. Portable power drills and such
use this chemistry and it sucks. If you leave your battery pack
on the charger, the battery will fail. If you charge it once a
week it will fail as well. Only people who use these tools daily
will find that they work when they need them! Same thing for
airplanes. If your Lear spends too much time sitting in the
hanger, the batteries fail. Doesn't everybody have a Lear?


Cheers,
Dick Johnson
Penguin : Linux version 2.6.16.4 on an i686 machine (5592.89 BogoMips).
New book: http://www.AbominableFirebug.com/
_
\x1a\x04

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Thank you.

Re: [IDEA] Poor man's UPS

[Christian Trefzer]

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On Mon, May 22, 2006 at 09:29:58AM -0400, linux-os (Dick Johnson) wrote:
> On Mon, 22 May 2006, Jan Knutar wrote:
> > I thought deep discharge cycles were unhealthy for lead batteries?
> 
> Yes. It's some of the more modern chemistries that need deep discharges
> because they tend to "remember".

And if you truly deep discharge them, they drop dead and won't remember
they've been charged. Topping off won't do any good either. So there's
some security margin your daily e.g.  LiIon appliance in your cellphone
will force upon you, in order to keep the battery alive. You can turn
the thing on over and over, but it will shut down on you after seconds.
It just won't suck the thing dry. And the charging process will be
stopped slightly before the battery is entirely full, to avoid
overcharge.

> Lead acid batteries, both wet cells and gel cells should be taken down
> to about 66 percent capacity and that's 66 percent capacity, not some
> arbitrary voltage. For instance, a 24 ampere-hour battery, fully
> charged at 25 degC, has a terminal voltage of 13.2 volts after the
> load is applied. Presumably it contains 13.2 * 24 * 3600 = 1,140,480
> joules (watt-seconds) of energy. You get to use 66 percent of this,
> i.e., 752,717 joules before it needs charging. You can't detect the
> charge state by looking at the terminal voltage! You need to actually
> measure the voltage and current during charge and discharge to
> maintain battery health. Otherwise, you just throw them away every
> year or so. The telephone company has lead-acid batteries that have
> been running for 50 years and they will be good "forever" because they
> carefully (automatically) maintain them.

Except for the slow and irreversible chemical transformations at the
poles, I guess. Acid is corrosive, after all. So with careful handling,
those things last a long time, but not forever, unfortunately. But the
approximation is good enough, anyway.

So it appears to me that those lead acid beasts make up a rather
constant source of DC - with other solutions the state can be measured
by means of voltage alone. But the circuitry might be a bit more
complicated for this exact reason. Do you by any chance know where I
might look for schematics of such circuitry? Any hint greatly
appreciated : )

Kind regards,
Chris

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Re: [IDEA] Poor man's UPS

[linux-os (Dick Johnson)]

On Mon, 22 May 2006, Christian Trefzer wrote:

> On Mon, May 22, 2006 at 09:29:58AM -0400, linux-os (Dick Johnson) wrote:
>> On Mon, 22 May 2006, Jan Knutar wrote:
>>> I thought deep discharge cycles were unhealthy for lead batteries?
>>
>> Yes. It's some of the more modern chemistries that need deep discharges
>> because they tend to "remember".
>
> And if you truly deep discharge them, they drop dead and won't remember
> they've been charged. Topping off won't do any good either. So there's
> some security margin your daily e.g.  LiIon appliance in your cellphone
> will force upon you, in order to keep the battery alive. You can turn
> the thing on over and over, but it will shut down on you after seconds.
> It just won't suck the thing dry. And the charging process will be
> stopped slightly before the battery is entirely full, to avoid
> overcharge.
>
>> Lead acid batteries, both wet cells and gel cells should be taken down
>> to about 66 percent capacity and that's 66 percent capacity, not some
>> arbitrary voltage. For instance, a 24 ampere-hour battery, fully
>> charged at 25 degC, has a terminal voltage of 13.2 volts after the
>> load is applied. Presumably it contains 13.2 * 24 * 3600 = 1,140,480
>> joules (watt-seconds) of energy. You get to use 66 percent of this,
>> i.e., 752,717 joules before it needs charging. You can't detect the
>> charge state by looking at the terminal voltage! You need to actually
>> measure the voltage and current during charge and discharge to
>> maintain battery health. Otherwise, you just throw them away every
>> year or so. The telephone company has lead-acid batteries that have
>> been running for 50 years and they will be good "forever" because they
>> carefully (automatically) maintain them.
>
> Except for the slow and irreversible chemical transformations at the
> poles, I guess. Acid is corrosive, after all. So with careful handling,
> those things last a long time, but not forever, unfortunately. But the
> approximation is good enough, anyway.
>
> So it appears to me that those lead acid beasts make up a rather
> constant source of DC - with other solutions the state can be measured
> by means of voltage alone. But the circuitry might be a bit more
> complicated for this exact reason. Do you by any chance know where I
> might look for schematics of such circuitry? Any hint greatly
> appreciated : )
>
> Kind regards,
> Chris
>

Telco used watt-meters and clocks to directly monitor the batteries.
In the event that the batteries had been floating for a month (not used
and trickle-charging), the timer would send them an equalizing charge
of about 10 amperes for 10 minutes. That would blast away any surface
corruption and bring the individual cells up to an equal terminal
voltage.

Modern chargers just don't bother unless the batteries are used for
medical equipment. In our portable CAT Scanners, we monitor current,
voltage, and time using a uP. This guarantees that once you start
a scan, the scan will complete (as required by regulatory agencies).

We also charge at a constant current until getting to the correct
terminal voltage. In other words, the charger is current-limited
until the voltage is correct, then it becomes voltage regulated.
The regulated voltage depends upon temperature and you can get
the numbers off from battery vendor's specifications. We don't
set an "equalizing charge" as telco did. We found with our specific
batteries it wasn't necessary.


Cheers,
Dick Johnson
Penguin : Linux version 2.6.16.4 on an i686 machine (5592.89 BogoMips).
New book: http://www.AbominableFirebug.com/
_
\x1a\x04

****************************************************************
The information transmitted in this message is confidential and may be privileged.  Any review, retransmission, dissemination, or other use of this information by persons or entities other than the intended recipient is prohibited.  If you are not the intended recipient, please notify Analogic Corporation immediately - by replying to this message or by sending an email to DeliveryErrors@analogic.com - and destroy all copies of this information, including any attachments, without reading or disclosing them.

Thank you.

Re: [IDEA] Poor man's UPS

[Christian Trefzer]

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On Mon, May 22, 2006 at 11:54:56AM -0400, linux-os (Dick Johnson) wrote:
 
> Telco used watt-meters and clocks to directly monitor the batteries.
> In the event that the batteries had been floating for a month (not used
> and trickle-charging), the timer would send them an equalizing charge
> of about 10 amperes for 10 minutes. That would blast away any surface
> corruption and bring the individual cells up to an equal terminal
> voltage.

Nice : )

> Modern chargers just don't bother unless the batteries are used for
> medical equipment. In our portable CAT Scanners, we monitor current,
> voltage, and time using a uP. This guarantees that once you start
> a scan, the scan will complete (as required by regulatory agencies).
> 
> We also charge at a constant current until getting to the correct
> terminal voltage. In other words, the charger is current-limited
> until the voltage is correct, then it becomes voltage regulated.

Constant-current / constant-voltage - just like Li-Ion batteries are
supposed to be charged. Talk about complexity ; )

IMHO battery "care" even in modern laptops sucks, so I'd rather have two
battery packs, one in use and the other one being charged. External
chargers don't seem to exist, AFAICS, so I'd very much like to build
one. Welcome to utopia...

> The regulated voltage depends upon temperature and you can get
> the numbers off from battery vendor's specifications. We don't
> set an "equalizing charge" as telco did. We found with our specific
> batteries it wasn't necessary.

Yup, the chemical processes inside the cells depend on temperature - do
your chargers monitor that as well?


Thanks a bunch,

Chris

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Re: [IDEA] Poor man's UPS

[Christian Trefzer]

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On Mon, May 22, 2006 at 04:04:14PM +0300, Jan Knutar wrote:
> On Monday 22 May 2006 01:40, Christian Trefzer wrote:
> > The logic should at least completely drain the battery before
> > recharging,
> 
> I thought deep discharge cycles were unhealthy for lead batteries?
> 
Guess the chosen terminology was a bit unlucky, with "completely" I
meant in fact "completely, within the constraints implied by the
technology used" ; ) So no deep discharge, but "as far as it gets
without killing the battery".

Kind regards,
Chris

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Re: [IDEA] Poor man's UPS

[Alan Cox]

> Guess the chosen terminology was a bit unlucky, with "completely" I
> meant in fact "completely, within the constraints implied by the
> technology used" ; ) So no deep discharge, but "as far as it gets
> without killing the battery".

Lead acid batteries should be kept well charged to avoid sulphation and
always full charged when recharging, preferably using a charger that
will do proper three step charging. "Cycling" a lead acid battery is a
great way to destroy it.

Alan

Re: [IDEA] Poor man's UPS

[Christian Trefzer]

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On Mon, May 22, 2006 at 04:40:58PM +0100, Alan Cox wrote:
> 
> Lead acid batteries should be kept well charged to avoid sulphation and
> always full charged when recharging, preferably using a charger that
> will do proper three step charging. "Cycling" a lead acid battery is a
> great way to destroy it.
> 

So it is better to use only one battery (or an array thereof) which is
sort of charged and discharged at the same time, or is this idea just as
screwed..? I don't have a degree in electronics, mind you : )

Might be easier to build something that keeps a battery well maintained
and switches in case of power outage. With large enough condensors to
bridge the gap, which would also iron out any peaks and stuff, this
should work pretty well.

Kind regards,
Chris

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Re: [IDEA] Poor man's UPS

[Matthias Schniedermeyer]

Christian Trefzer wrote:
> On Mon, May 22, 2006 at 04:40:58PM +0100, Alan Cox wrote:
> 
>>Lead acid batteries should be kept well charged to avoid sulphation and
>>always full charged when recharging, preferably using a charger that
>>will do proper three step charging. "Cycling" a lead acid battery is a
>>great way to destroy it.
>>
> 
> 
> So it is better to use only one battery (or an array thereof) which is
> sort of charged and discharged at the same time, or is this idea just as
> screwed..? I don't have a degree in electronics, mind you : )
> 
> Might be easier to build something that keeps a battery well maintained
> and switches in case of power outage. With large enough condensors to
> bridge the gap, which would also iron out any peaks and stuff, this
> should work pretty well.

You just described the working-principle of a "line-interarctive" UPS.
AFAICT this is the most used UPS-type, at least for every "small" UPSes 
i've seen in the last few years.




Bis denn

-- 
Real Programmers consider "what you see is what you get" to be just as
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated,
cryptic, powerful, unforgiving, dangerous.

Re: [IDEA] Poor man's UPS

[Christian Trefzer]

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On Mon, May 22, 2006 at 06:15:24PM +0200, Matthias Schniedermeyer wrote:
> You just described the working-principle of a "line-interarctive" UPS.
> AFAICT this is the most used UPS-type, at least for every "small" UPSes 
> i've seen in the last few years.

Exactly, and since I cannot afford to buy one I'd have to build it
myself using mainly car batteries. The most complex part would be to
charge the batteries in a way that won't kill them over time. Building
such stuff into the PSU after the secondary coil and AC/DC converter
would save the double-conversion loss, therefore making this ideal for a
single machine. But I'm still brainstorming, lacking both money and
time.

Kind regards,
Chris

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Re: [IDEA] Poor man's UPS

[Avi Kivity]

Christian Trefzer wrote:
>
> Exactly, and since I cannot afford to buy one I'd have to build it
> myself using mainly car batteries. The most complex part would be to
> charge the batteries in a way that won't kill them over time. Building
> such stuff into the PSU after the secondary coil and AC/DC converter
> would save the double-conversion loss, therefore making this ideal for a
> single machine. But I'm still brainstorming, lacking both money and
> time.
>

Led/acid batteries are dangerous. Don't use them unless you know exactly 
what you are doing.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.

Re: [IDEA] Poor man's UPS

[Martin J. Bligh]

>> Exactly, and since I cannot afford to buy one I'd have to build it
>> myself using mainly car batteries. The most complex part would be to
>> charge the batteries in a way that won't kill them over time. Building
>> such stuff into the PSU after the secondary coil and AC/DC converter
>> would save the double-conversion loss, therefore making this ideal for a
>> single machine. But I'm still brainstorming, lacking both money and
>> time.
> 
> Led/acid batteries are dangerous. Don't use them unless you know exactly 
> what you are doing.

Buy an intelligent charger for an RV. They're designed to do pretty much
exactly that (deep cycle marine batteries, probably).

M.

Re: [IDEA] Poor man's UPS

[Nuri Jawad]

On Mon, 22 May 2006, Christian Trefzer wrote:
>
> Exactly, and since I cannot afford to buy one I'd have to build it
> myself

I bought a used APC Back-UPS Pro 1400 VA from Ebay for 60 EUR. Batteries 
in top condition, like new.
I didn't follow the complete thread, but.. you must have a lot of time on 
your hands =).

Regards, Nuri

Re: [IDEA] Poor man's UPS

[Christian Trefzer]

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On Mon, May 22, 2006 at 09:46:44PM +0200, Nuri Jawad wrote:
> On Mon, 22 May 2006, Christian Trefzer wrote:
> I bought a used APC Back-UPS Pro 1400 VA from Ebay for 60 EUR. Batteries 
> in top condition, like new.
> I didn't follow the complete thread, but.. you must have a lot of time on 
> your hands =).
> 

Not quite, unfortunately. Just some strange thoughts at times, that's
about it. 

So far the quality of the electricity network here is quite in order, if
not perfect. But since it's all about money these days, that quality
will drop sooner or later. Until that time has come I'd better be in a
position to afford the UPS and the space to tuck it in. Anyway, all this
self-made consideration is more out of interest. In case I'd actually go
into production, I know a few guys I can ask in advance whether what I
want to do is entirely insane or actually worth thinking over in terms
of a fun-to-do project.

Kind regards,
Chris

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Re: [IDEA] Poor man's UPS

[Jeff V. Merkey]

Christian Trefzer wrote:

>On Mon, May 22, 2006 at 04:40:58PM +0100, Alan Cox wrote:
>  
>
>>Lead acid batteries should be kept well charged to avoid sulphation and
>>always full charged when recharging, preferably using a charger that
>>will do proper three step charging. "Cycling" a lead acid battery is a
>>great way to destroy it.
>>
>>    
>>
>
>So it is better to use only one battery (or an array thereof) which is
>sort of charged and discharged at the same time, or is this idea just as
>screwed..? I don't have a degree in electronics, mind you : )
>
>Might be easier to build something that keeps a battery well maintained
>and switches in case of power outage. With large enough condensors to
>bridge the gap, which would also iron out any peaks and stuff, this
>should work pretty well.
>
>Kind regards,
>Chris
>  
>
You know, these old lead acid batteries are a fire hazard, not to 
mention they produce free hydrogen gas when discharging to charging.

Guys, stick to nicads or a fuel cell to avoid burning down your house or 
the neighborhood.  Ever see a lead acid battery explode?  I have.  It 
throws sulphuric acid all over the place.

Jeff

Re: [IDEA] Poor man's UPS

[Neil Brown]

On Sunday May 21, pgquiles@elpauer.org wrote:
> 
> A short description would be "continuous system hibernation". Say you are 
> running Firefox, writing an e-mail in mutt and compiling the next X.org 
> release. The power goes off, your computer crashes or something happens and 
> you lose everything you were doing (yes, sadly you haved saved your e-mail as 
> a draft yet).

You need an editor that auto-saves regularly.  May I suggest emacs ;-)

One of my biggest grips about the current fad of web-based
interactions is that you get to use the editor built into your browser
rather than your editor of choice - and the editor built into firefox
is pretty lame....
Now if only firefox could embed a window from my running emacs ....

Or to put it another way:  you don't need to save the whole system
state: just save the bits you actually need to save.

NeilBrown

Re: [IDEA] Poor man's UPS

[Chris Wedgwood]

On Mon, May 22, 2006 at 09:02:51AM +1000, Neil Brown wrote:

> Now if only firefox could embed a window from my running emacs ....

actually, it can somehow

Re: [IDEA] Poor man's UPS

[Neil Brown]

On Sunday May 21, cw@f00f.org wrote:
> On Mon, May 22, 2006 at 09:02:51AM +1000, Neil Brown wrote:
> 
> > Now if only firefox could embed a window from my running emacs ....
> 
> actually, it can somehow

Come on!!! you cannot just leave me dangling like that :-)
Knowing that it can be done, but not how...
Is it a config option, or do I have to write pages of XUL, or do
I have to bribe some developer or .... ???

NeilBrown

Re: [IDEA] Poor man's UPS

[Björn Steinbrink]

On 2006.05.22 10:23:28 +1000, Neil Brown wrote:
> On Sunday May 21, cw@f00f.org wrote:
> > On Mon, May 22, 2006 at 09:02:51AM +1000, Neil Brown wrote:
> > 
> > > Now if only firefox could embed a window from my running emacs ....
> > 
> > actually, it can somehow
> 
> Come on!!! you cannot just leave me dangling like that :-)
> Knowing that it can be done, but not how...
> Is it a config option, or do I have to write pages of XUL, or do
> I have to bribe some developer or .... ???

Maybe this does the trick?
http://mozex.mozdev.org/

Heard about it a few days ago, didn't try it out yet, but sounds like it
is what you're searching for.

HTH
Björn

Re: [IDEA] Poor man's UPS

[Neil Brown]

On Monday May 22, B.Steinbrink@gmx.de wrote:
> On 2006.05.22 10:23:28 +1000, Neil Brown wrote:
> > On Sunday May 21, cw@f00f.org wrote:
> > > On Mon, May 22, 2006 at 09:02:51AM +1000, Neil Brown wrote:
> > > 
> > > > Now if only firefox could embed a window from my running emacs ....
> > > 
> > > actually, it can somehow
> > 
> > Come on!!! you cannot just leave me dangling like that :-)
> > Knowing that it can be done, but not how...
> > Is it a config option, or do I have to write pages of XUL, or do
> > I have to bribe some developer or .... ???
> 
> Maybe this does the trick?
> http://mozex.mozdev.org/
> 
> Heard about it a few days ago, didn't try it out yet, but sounds like it
> is what you're searching for.

Coooool, thanks.

It doesn't seem to pass a window-id so I cannot get emacs to place
it's window exactly over the text-area (not that I'm sure emacs can be
told to do that...) but it is certainly close enough.

Much obliged :-)

NeilBrown

Re: [IDEA] Poor man's UPS

[Pavel Machek]

Hi!

> This is an idea a had some time ago. It might be a waste of time or it might 
> be a good idea, you decide.

Well, it depends on "are you willing to work on it"?

> The "continuous hibernation" is some kind of memory snapshots taken, say, 
> every 5 minutes. The next time your system starts after a crash, it'd say "oh 
> oh, looks like something went wrong" and offer you a list of the last N (for 
> instance, 4) snapshots and you can recover your system to the very same state 
> it was before power went off or your dog unplugged your CPU. It might even 
> ask you which individual applications you want to start from that snapshot:  
> maybe you don't want to start Quake 3.

See suspend.sf.net and probably dm snapshotting functionality. Most of
what you want can be done today, and in userspace.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html