How Fast Can We Make It Boot?

[multiplex]

Interesting article about making desktop Linux boot up in five seconds over here:
http://lwn.net/Articles/299483/

Now five seconds is crossing into what I'd call very excellent, so I was wondering how applicable this would be to the Pandora?
I'd expect the SoC hardware to be fast to initialize, and since the hardware is fixed you can tweak the boot process a lot. On the other hand, I guess booting from SD cards is slower than having a proper SSD.

Does anyone have any experience with quick-booting Linux solutions?

 

[bitz_dv]

Kind of off topic, but would the faster SD cards make a huge difference? Like the Sandisk extreme III 30mb/sec versions over the 20mb/sec versions. Does the hardware support the full range of speeds to accommodate for the crazy fast cards is what I am asking

 

[Tom`]

Kind of off topic, but would the faster SD cards make a huge difference? Like the Sandisk extreme III 30mb/sec versions over the 20mb/sec versions. Does the hardware support the full range of speeds to accommodate for the crazy fast cards is what I am asking

To some extent - the theoretical maximum is 24 MB/s or so, but we won't hit that. 13-15 MB/s would be considered very good, I guess.
I don't know how much difference that would make to the boot speed, because I don't know whether the SD speed is the bottleneck or to what degree it affects the boot process.
It would increase the speed of restore-from-disk (i.e. hibernation), but that would probably be less than ten seconds in any case, so the increase might not be worth the price.

 

[bitz_dv]

Kind of off topic, but would the faster SD cards make a huge difference? Like the Sandisk extreme III 30mb/sec versions over the 20mb/sec versions. Does the hardware support the full range of speeds to accommodate for the crazy fast cards is what I am asking

To some extent - the theoretical maximum is 24 MB/s or so, but we won't hit that. 13-15 MB/s would be considered very good, I guess.
I don't know how much difference that would make to the boot speed, because I don't know whether the SD speed is the bottleneck or to what degree it affects the boot process.
It would increase the speed of restore-from-disk (i.e. hibernation), but that would probably be less than ten seconds in any case, so the increase might not be worth the price.


Ahh well, I actually ordered 3 4gb sdhc 30mb/sec cards right before stumbling upon the Pandora and deciding to purchase. I also have some of the same cards currently, only the 20mb/sec versions so I will have to do some tests when I get my Pandora to see if the theoretical 4 extra MB/s makes a huge difference in boot time and restore from disk.

Also if anyone is interested, it seems Sandisk is having a huge rebate event and great prices can be had from beach audio or adorama. The 4GB SDHC cards are $5 each after rebate for 3. Check out the slickdeals page with links here

 

[frozenflame108]

I'm pretty sure that the pandora will boot off of the internal memory, not one of the sd cards.

 

[cosam]

I'm pretty sure that the pandora will boot off of the internal memory, not one of the sd cards.

By default, yes, but you'll be able to boot from SD if you like.

 

[CyruzDraxs]

I just hope it boots faster than my Cowon A3. It scans the entire filesystem for changes every bootup...40,000 mp3s make it a very slow process. It takes a good minute and a half to boot. >.>

 

[Lorkile]

A nice few second boot would be sweet, though I'm guessing that if it gets anywhere near that 100 hours for mp3 playback that mine will be on more often then not.

 

[chris_r]

I'm guessing the pandora team has already tested this, but as far as I know loading the system from a ramdisk could speed up the boot.

 

[mali]

If there will be a decent power management implemented, like in maemo, the actual boot time is relatively pointless. With its high capacity battery it will easily achieve a whole month of on-time with the display turned off with one charge without the need of shutting off completely. The OMAP is really amazingly efficient.

 

[grasshoppir]

want both

 

[Tor]

QUOTE
If there will be a decent power management implemented, like in maemo, the actual boot time is relatively pointless. With its high capacity battery it will easily achieve a whole month of on-time with the display turned off with one charge without the need of shutting off completely. The OMAP is really amazingly efficient.
+1

Yep. Unless you do low-level testing&development, or there's some problem, there shouldn't even be a reason to reboot the device at all. Not that it won't happen now and then, but it shouldn't be a daily occurrence. I mean, my desktop linux systems often reach uptimes of half a year or more.. I have one here with 622 days of uptime. I imagine the Pandora could easily have uptimes of several weeks (a new handheld like this probably needs more rebooting due to a problem or something than a desktop).

Just put it on a charger every now and then.

 

[sebt3]

As the hardware is fixed, there will not have any initrd. this will save time. no need to detect hardware on boot time : it's fixed. (but hald started during boot time would be fair, so usb device will be probed later on).
I'm sure that the main distribution will be very limited. No useless deamon &co. So basically, boot process will be :
Kernel startup,
hardware initialisation,
kdrive Xserver startup,
gmenu startup

All this should (have to) fit within the 10 sec time frame. But I'm all for the following solution :
- cpufreqd set on the ondemand scheduler (which mean omap CPU support frequency scaling)
- suspend to ram enabled,
- suspend to disk on (err to sdcard )

all these should make the boot process painless and near instant. My destops are setted this way and this is lovely. I only reboot for real when I change my kernel (or libc) else I use S3 or S4.

 

[Bramrash]

I can make it boot in over 9000!!!!!

....sorry everyone, I'll leave.

Actually, as long as it's not ridiculous I dont mind what the boot time is. I got my gp2x near the start when it took 30 secs to boot. Just gives you time to pick your nose/check your testicles.

 

[multiplex]

Actually, as long as it's not ridiculous I dont mind what the boot time is. I got my gp2x near the start when it took 30 secs to boot. Just gives you time to pick your nose/check your testicles.

I do believe this would make an excellent sales pitch.
"Scientific studies have shown that statistically, users of the Pandora portable console have cleaner noses and less risk of testicular cancer."

It's true that we'll hopefully have good enough power management to just shut the lid and forget about it... I guess I'm thinking of it like the DS, where I have to power cycle it just to switch applications.

As for suspend to disk, while it's nice in that it saves your application's state for you, and great for when you suspend-to-ram and forget about it until the battery runs out, I think it can actually be slower than a fresh boot, in that you'd need to read in the entire contents of ram again. Disk I/O is usually a bottleneck for these things.

 

[Chip]

With its high capacity battery it will easily achieve a whole month of on-time with the display turned off with one charge without the need of shutting off completely.
Two months in suspend-to-RAM mode. Recovery from STR should be nearly instantaneous.

 

[mali]

With its high capacity battery it will easily achieve a whole month of on-time with the display turned off with one charge without the need of shutting off completely.
Two months in suspend-to-RAM mode. Recovery from STR should be nearly instantaneous.


That's really amazing

 

[MarkoeZ]

*linux newb talking

about skipping hardware detection: does that not skip the usb hardware?

Edit: Missed the usb part, im on my mobile and scrolled too fast ("Damn i want my pandora!" moment... ; )