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LPC: Booting Linux in five seconds

LPC: Booting Linux in five seconds

Posted Sep 23, 2008 13:29 UTC (Tue) by lbt (subscriber, #29672)
In reply to: LPC: Booting Linux in five seconds by jzbiciak
Parent article: LPC: Booting Linux in five seconds

> In my mind, suspend is something of a hack to get around awful boot times,
> and it's still flaky for some users. It also doesn't help you at all when
> you have to install OS updates that require a reboot.

OK - that's your use...

*I* have 6 virtual desktops, eg:
1 with email, a browser window with 15-20 ever changing tabs,
a dev desktop or 2 in various states of compile/dev for multiple projects
an 'office' desktop with maybe OO Writer or Calc or QCAD or...
an admin desktop with windows to various boxen

I have a continually logged on experience interrupted by phone calls, sleep, food, social life, holidays etc - but it's nice to save power at night or when I go for food or go out so I want to hibernate (and I do - I only login/reboot when I choose to upgrade the kernel)

For those who argue that each app should do 'restore state' - why? Debian has what, 22,000 packages many of which would need to be able to restore state. Or we could use hibernate and get them all for free... Hmmm hard choice...

As for "install OS updates that require a reboot." - are you on Linux? This just doesn't happen with any meaningful frequency.


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LPC: Booting Linux in five seconds

Posted Sep 23, 2008 16:48 UTC (Tue) by bronson (subscriber, #4806) [Link]

Are you talking about suspend or hibernate? Resuming from suspsend takes about 9 seconds on my Thinkpad T42p, while resuming from hibernate takes 1.5 mins. This is unfortunate because cold boot takes less than a minute... I tend to suspend/resume a lot and never ever hibernate.

When Linux supports process suspend/resume, hopefully resuming from hibernate becomes:
- boot in 5 secs
- restore your suspended apps

I can't wait for containerization to hit.

LPC: Booting Linux in five seconds

Posted Sep 23, 2008 18:55 UTC (Tue) by jwb (guest, #15467) [Link]

Why does your resume from suspend take so long? On my ThinkPad it takes less than one second.

LPC: Booting Linux in five seconds

Posted Sep 23, 2008 20:18 UTC (Tue) by bronson (subscriber, #4806) [Link]

No idea... The CD-ROM drive spins up (no disk in it though), there's some beeping from the speaker, after 3 seconds the backlight turns on, after 5 it switches to a real video mode, and it spends the last second or so drawing the password dialog.

I don't mind too much, 8 seconds is tolerable. At least it never crashes!

LPC: Booting Linux in five seconds

Posted Sep 25, 2008 1:56 UTC (Thu) by deleteme (guest, #49633) [Link]

That's awfully fast, it's more like 1.5 - 3.5 seconds here. The disks starts to spin the screenblinks and take a while to become something usefull-

LPC: Booting Linux in five seconds

Posted Sep 25, 2008 2:49 UTC (Thu) by jwb (guest, #15467) [Link]

Well maybe you're right, because I just took a video of my computer waking from sleep and it takes 6 seconds. However, the time between when the backlight comes on and when the unlock dialog appears is a split second. I guess I was mentally attributing the remainder of the time to the hardware/BIOS.

Which brings us back around to the article. The five seconds of booting does not include the time between power-on and when GRUB hands off to Linux.

LPC: Booting Linux in five seconds

Posted Sep 26, 2008 2:12 UTC (Fri) by njs (subscriber, #40338) [Link]

I thought restore from hibernate spent most of its time reading the (potentially multi-gigabyte) memory image from disk. Booting doesn't need to load 500 megabytes of firefox into memory, etc.; is there some reason to think that restoring your individual apps would be faster than restoring the hibernate memory image?

LPC: Booting Linux in five seconds

Posted Sep 26, 2008 17:09 UTC (Fri) by bronson (subscriber, #4806) [Link]

Because -- in theory -- you wouldn't have to restore every application, (don't worry about freezing the memory used by all those useless panel apps). And the apps themselves could be smarter (Firefox wouldn't try to persist its in-memory caches). Crash-only apps could just be terminated and re-launched (IM clients, mail clients, etc), no need to write them all out.

I admit, it's all speculation at this point. :)

LPC: Booting Linux in five seconds

Posted Sep 23, 2008 17:04 UTC (Tue) by jzbiciak (✭ supporter ✭, #5246) [Link]

Ubuntu seems to push kernel updates that want a reboot every few weeks. That said, I usually push it to a couple months before I do reboot.

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