Release SuperZaxxon - Beta 2 released


I agree it would be nice if it worked with PNDs mounted, but unfortunately I don't think this is ever going to work due to technical issues.

Why doesn't this work?:


sync card


stop PND


unmount card


suspend


---


resume


mount card


allow PND to continue


The pnd would segfault pretty soon after if you swapped cards during suspend, but the card wouldn't get corrupted, would it?
 
When you unmount, all open files PND has opened, even it's working directory become invalid, the PND would have to reopen all it's files after resume, and no pnd ever does that, i.e. nothing expects their open files to suddenly disappear in thin air. Theoretically the system could transparently reopen all files on resume and restore their state (seek pointers, etc) but Linux has no such functionality.
 
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So there's no way to start/stop access to files without i) corrupting things or ii) the pnd finding out?
 
Using the old kernel on HF7B2, should TV out work? I've tried two different cables that I've used successfully in the past and now all I get is Black & White (poor quality as well) sometimes I get off colors using a composite cable. The one cable from Peca I have has both composite and S-Video, neither will work, and the cable I have from Askarus only has Composite, and this doesn't work well either.


Can anyone confirm or deny any of this as well?
 
HF7B2 + old kernel +tv out works fine here.


Black and white happens with new kernel.
 
Again, without the ability to sleep/wake with active PNDs, this standby just a mere tech demo.


Which is ok, as an intermediary step (beta test), towards the ultimate goal to have the ability to sleep/wake with active PNDs.


Linux must have the required functionality, as I can put my Ubuntu laptop to sleep with open applications, and just resume fine later after wake-up.


Or does the PND-standard/system need changes to allow sleep/wake?
 
Again, without the ability to sleep/wake with active PNDs, this standby just a mere tech demo.


Which is ok, as an intermediary step (beta test), towards the ultimate goal to have the ability to sleep/wake with active PNDs.


Linux must have the required functionality, as I can put my Ubuntu laptop to sleep with open applications, and just resume fine later after wake-up.


Or does the PND-standard/system need changes to allow sleep/wake?

Isn't the difference that your Ubuntu box does not run programs off removable media?


Presumably it would work as long as the user promises not to remove the cards while its suspended?
 
HF7B2 + old kernel +tv out works fine here.


Black and white happens with new kernel.
How's about this one....


German Pandora, gives me Black & White using Old Kernel on TV-Out cables. Tried with 2 TV Out cables, same results, although I might have saw full color for 5 seconds with Askarus cable at some point, then when I grabbed the audio cables to hook up, it lost it. I'm going to drop the battery out for a 10 minute Pandora Time Out and see if that resets some tomfoolery because I did boot yesterday into Experimental kernel. I will look into this further and report back. I think all the connections are good all around, but will dobule check.


US/UK Pandora, TV Out is working fine using composite cable from Askarus. Obiviously using old kernel.
 
It sounds like you're using the new kernel even without having selected it !


uname -r will show you the version.
 
How do other distros do it? I can start playing a video from an external hard drive, suspend my computer, even go so far as to turn off and on that external hard drive, then un-suspend my computer and the video will resume playing with no apparent problem. Is this a function of the kernel or is this mplayer catching that the file descriptor has vanished and manually re-opening it at the same spot?
 
Again, without the ability to sleep/wake with active PNDs, this standby just a mere tech demo.

Not really.


While that would be nice, the new kernel power saving features are a lot more then a mere tech demo.


Right now, if I know I'm not using my Pandora for a few hours, I close the running apps and go into standby mode.


With about 10% power loss per day, this is pretty awesome.


Instead of rebooting, I flick the switch and have the system back in working state within a few seconds.


If I just want to take a small break from gaming, I simply pause my game and close the lid.


While it's not as good as the standby mode, it's already using way less power than when using the low-power mode of the old kernel.


It's about 2 - 3% battery loss per hour.


Pretty awesome for me, though the current downside is that if I accidentally go into standby-mode while a game is running, the PND will crash... but that can be enhanced:


If PNDs are running, go into old low-power mode. Would probably need 2% battery power per hour, which is still great.


If no PNDs are running, go into standby mode. That should be about 0,5 - 1% per hour.


So this is the worst achievable case right now. The best would be full standby mode even with PNDs running, but this surely is no easy task.
 
I usualy close apps if I don't use them, so I can live with that. Even on my PC I bareley use multitasking.


Some days ago my buddy showed me his new iPod Touch, latest model I guess. Really impressive tech these flat little thingy has. My first ever experience with an Apple iPod. But it is weird because it doesn't close an app that easy, you have some taskbar on the bottom with alot of active apps you were using. It just minimize everything. You can touch and continue any of them at any time, I wonder how this is managed. It also should work with powersave but I'm not sure how the device handles this. Apple seems to have some talented people in there, I never had expected this. :D
 
When suspending, ensure that you remove any swap that you may have had open. If you don't you'll need to hard reset when you restore anyway. :p
 
I usualy close apps if I don't use them, so I can live with that. Even on my PC I bareley use multitasking.


Some days ago my buddy showed me his new iPod Touch, latest model I guess. Really impressive tech these flat little thingy has. My first ever experience with an Apple iPod. But it is weird because it doesn't close an app that easy, you have some taskbar on the bottom with alot of active apps you were using. It just minimize everything. You can touch and continue any of them at any time, I wonder how this is managed. It also should work with powersave but I'm not sure how the device handles this. Apple seems to have some talented people in there, I never had expected this. :D

The magic is contained in *nix since many years and called process suspend, aka SIGTSTP and SIGSTOP. You can send (nearly) anything to sleep in a blink of an eye, leaving it only occupying RAM, but using no CPU cycles. iPod probably does not always to a full stop I guess, as some applications still work in the background. This pretty surely works on the pandora as well as any *nix. It does NOT take into account that it's working directory vanishes, which will happen if you remove the SD-card (when entering sleep). So I am pretty sure, IF you copy your PNDs to the local drive (and the sleep does not force-unmount the PND) it will survive the sleepmode.


The iPod is no magic at all at this point. It simply does not have to considerate external storage.
 
Dear jottt!


1) Thank you for being another supporter, that standby with active PNDs is desirable.


2) The functionality of iOS (and Mac OS X 10.7 Lion), which you mention, is not only standby functionality in the classical sense, but an extended technique, called "Automatic Termination" (Apple Dev Doc, Ars Technica Review). Apps serialize their current state (save their whole state to permanent (disk or flash) storage), and set a flag "ready for termination", and the OS decides when to kick them out of memory, and when it is needed again (user switches to this app, or it partially gets visible again), the OS triggers the app again, and its initialisation recreates its state from the serialization from permanent storage, and the user finds his program in the state where s/he left it.


Nr.2 is unrealistic to realize for the Pandora, as the PNDs come in a flavor of different programming/API styles,


but nr.1 should be achievable, as WizardStan reports, and as I know of from all kind of Linux devices.
 
Again, without the ability to sleep/wake with active PNDs, this standby just a mere tech demo.

Not really.


While that would be nice, the new kernel power saving features are a lot more then a mere tech demo.


Right now, if I know I'm not using my Pandora for a few hours, I close the running apps and go into standby mode.


With about 10% power loss per day, this is pretty awesome.


Instead of rebooting, I flick the switch and have the system back in working state within a few seconds.


If I just want to take a small break from gaming, I simply pause my game and close the lid.


While it's not as good as the standby mode, it's already using way less power than when using the low-power mode of the old kernel.


It's about 2 - 3% battery loss per hour.


Pretty awesome for me, though the current downside is that if I accidentally go into standby-mode while a game is running, the PND will crash... but that can be enhanced:


If PNDs are running, go into old low-power mode. Would probably need 2% battery power per hour, which is still great.


If no PNDs are running, go into standby mode. That should be about 0,5 - 1% per hour.


So this is the worst achievable case right now. The best would be full standby mode even with PNDs running, but this surely is no easy task.

Of course I respect the development achievement, no question!


1) If normal operation is more power efficient, then this is a worthy success per se.


2) But that I consider the standby as a usability success, will only be when active PNDs can be pauses/resumed.


Having to quit all apps:


1) is time consuming (wait for termination)


2) will destroy my current state (many games do not allow save state at all or at any time), thus is NO means for pausing/resuming


3) gives the "resume OS (not apps!) in just 5 seconds" advantage indeed, but with the disadvantage of consuming power, compared to a full shutdown/restart (which in total may take ~90 seconds)


Small break from gaming:


1) If this is < 30min, then the "low power mode" 's power loss is acceptable


2) If it is for a quarter/half a day (think about pause/resume intervals like: transit to work, lunch break, transit back home), then the low power mode loss is unacceptable, a (OS + PND) standby would be desirable.
 
I don't understand why apps can't just be taught to listen to SIGSTOP/SIGSTP and then have something (daemon? kernel?) send these signals on suspend and resume. Oh, I guess I understand .. its something we'd have to get everyone to implement, or?
 
2) The functionality of iOS ...

Thanks for clarification :) I don't have any iOS device but still good to know. Android, by the way, is also capable of deep sleeping with open apps on SD. Android however does not like it, when you remove the card that an App is stored on (not surprisingly). Hard to compare though as Android has quite a few more developers with a lot more time on their hands and PNDs are handled differently...p.e. Android's ipk where not designed to be movable with their data...same goes for iOS I assume. Both devices don't have to care about where their data is, when they need it again...it can't leave.


Talking about standby with open apps:


I can see that being nice and handy and quite a few people find this desirable. I still would never call it just a "tech demo" the way it is right now. It might depend on what you're doing, but at the moment my biggest "issue" with the pandora was the fact that I had to shutdown and reboot when I did not use it for some time. I don't really mind reopening my apps that much. When I pause for half an hour within a game, I don't mind the higher power consumption of "lid-closed-sleep". When I go to sleep, I don't need my game suspended.


Sooo my point of view: Low-Power at all: Big step ~ Low-Power like a cellphone: Icing on the pandacake.


Of course there are still many tweaks and configurations to be done to make it "better". I prefer a solid "base" compared to a bling-bling-version that misbehaves from time to time ;)
 
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