How To Speed Up Linux Booting

An anonymous reader writes "A common complaint about Linux is the amount of time the operating system takes to start. Like Linux itself, there are plenty of options and lots of flexibility for boot-time optimization. From dependency-based solutions like initng to event-based solutions like upstart, there's an optimization solution that should fit your needs. Using the bootchart package, you can dig in further to understand where your system is spending its boot time to optimize even more."

Comments

Boot time not an issue.

[AmIAnAi]

I thought one of the arguments for linux was that you didn't need to reboot - like you do with Windows. So the boot time should not matter :-)

Re:Boot time not an issue.

[arth1]

Indeed. The boot time of a system you boot once a year is rather irrelevant.
Laptop, you say? Hibernate, don't boot!

What's more interesting is to reduce the login time and start-up time for applications. prelink is your best friend here. Make sure that all your apps are compiled for position independent code (PIC), and prelink them. Lots of time saved, at the expense of larger binaries.

Regards,
--
*Art

Re:Boot time not an issue.

[Micah]

In my Kubuntu Feisty install, Hibernate takes about as long as shutting down and starting it back up about as long as a normal start.

Of course, all the apps are still there so that helps. But it's not nearly as efficient as, say, a Mac where you can close the lid any time, open it back up again and have it right there in 2 seconds.

Re:Boot time not an issue.

[Bert64]

But as you said, for the first few minutes after boot, windows is thrashing the disk and running slower... Sometimes it even does ridiculous things, like closing the start menu while your trying to select something from it, or ignoring some mouse clicks.
You could make linux start in the same way, modify the init scripts to start XDM first, and everything else later, in which case you'd have the same appearance of fast booting.

Re:Boot time not an issue.

[cmacb]

To be fair, my Windows box boots pretty quick; I think the time between power on and desktop is somewhere in the region of 50 seconds.

The only reason you can say that 50 seconds seems pretty quick is that most of us remember when several minutes was he norm. The interesting thing is that as feature creep in all operating systems has continued (you can't have glass windows in one OS without users of all other OSs feel the "need" for it too after all) has kept boot time longer than we would like, even though hardware speeds have continued to increase by orders of magnitude.

Can you imagine how long an XP boot (or Ubuntu for that mater) would take on an old 386 system with a sluggish hard drive and not a lot of memory (if such a thing were even possible)? Hours I would guess, and you would shake your head wondering if your hard drives MTBF would get you through the process.

In the future will it take four or eight processors in a box to keep the lag down to 50 seconds? Should we take any delight in the fact that Windows boot will be sped up again only by special code to pre-load parts of the OS into flash ram before shutdown? I don't. I'd much prefer to see an almost-instant-on OS that didn't depend on special hardware tricks but rather because the architects actually designed the bloody thing for a change. Aint gonna happen though. If there are still any really smart people working at MS I'm sure they are working on the next great Google/Sony/IBM/Oracle killer or something. Faster boots would benefit ALL Windows users, not just MS only shops. We can't have that now can we?

It's a good sign when an OS rarely needs to be booted, which is at least the case with Linux and OS X (can't speak for Vista). I leave my machines running all the time, even my desktop has laptop innards, so they go into a low power state when not used for a while. What I do to clean up any cruft that has built p running poorly behaved applications is to reboot when I am done using the computer for a while. That way I don't have to sit around and wait for the process to complete. the machine reboots, sits there for thirty minutes and then goes to sleep. It's ready to go and "freshly" booted the next time I need it. Of course if you like to keep a lot of memory hogs autoloaded and running in the background this system may not work so well.

Re:Boot time not an issue.

[TheNetAvenger]

guess the point is that we *should* be switching our machines off whenever possible as opposed to leaving them running for no reason. The home user isn't going to be persuaded by Linux if he/she has to wait a long time to actually get a computer into a usable state*.


Yes, but rebooting should not be the option people are using. Go the power management route and do things like enter low power mode, or do a full suspend to disk (hibernate).

Rebooting really should not the solution to using less power, especially with the Power management concepts can be automated based on idle usage, turn themselves back on to run tasks and back off.

I got into this habit from carrying a couple of laptops full time, and it is something I carry over to my personal desktops as well.

People need to just exchange Off with Hibernate in their minds. Even with Windows, which doesn't have bad boot times, it is just easier to tell the system your power button is the hibernate button, and hit it and go on my way. Then turning on the computer is a few seconds and I don't have to worry about what I left running ever. Especially with someone like me that has tons of crap running all the time, including several VMs which I don't have to individually suspend to disk if I were to shut down the computer everytime.

And thank god OSX finally added a true hibernate in 10.4 on their notebooks, cause not having it about drove me flipping insane.

So now that 99% of all OSes have ok power management, rebooting should be a thing of core updates only.

PS
The boot times on Linux are really not bad in a default install on most distributions. And people shouldn't take this article as evidence that Linux is slow or sucks at boot times.

However, I do applaud the efforts to improve boot times, and wish there was a bit more generic optimization like people from the Windows world are use to.

Vista for example monitors the last 5 boot times, and will continually adjust disk layout and process order, etc to continue to speed up boot times. There is no reason all OSes couldn't add a generic form of optimization like this.

Customize the Bootscript, Trim the Fat

[Old Duck]

Most bootscripts are very generic in that they will try to load all sorts of RAID drivers, various services that are not needed, special fonts, etc.. I've gone in on my computers and wrote a very simple, quick, and to-the-point bootscript (easy to do with a little BASH knowledge), and my system boots up remarkedly fast. Granted, my bootscript isn't very portable, but one of the benefits of Linux is the ability to customize it.

Another trick is to prelink files and let KDE (if that is what you use) know about it. Even the startkde script can be long and drawn out, so trimming the fat and only including what's needed on your system can make a big difference. I've shaved over 13 seconds off a boot sequence by writing a minimum bootscript for my hardware, and that was using a relatively fast distro to start with.

-Mike

Re:An Uninformed Question

[CastrTroy]

Or maybe he's just counting the time until the computer is actually usable. With Linux once the computer is booted, and you see the desktop, it's ready to use. With windows, it takes another 20 seconds (at least) after the desktop appears for it to actually become usable.

Lots of always-on selfishness

[linvir]

Anybody else appalled by the amount of people saying "just don't turn it off"?. I know I am. It's shocking for various reasons:

1. It's an unnecessary, unethical waste of energy.
2. It's an unnecessary security risk to leave so much of your sensitive data connected to the internet completely unattended.
3. If you do get compromised, there is then the ethical issue of the amount of spam/DDoS your box can be used for by the time you realise what has happened.
4. It's a poor solution to the problem of long boot times. A better solution would be to man up and learn some fucking patience.
5. It uses up your machine's useful lifespan much more quickly at no significant gain to you.
6. It's yet another electrical appliance always on and always ready to set off your smoke alarm or even start an electrical fire.

If you leave your computer on 24/7 just for convenience, then perhaps you ought to consider the possibility that you are a spoilt rich selfish pussy and not the infallible sysadmin you undoubtedly believe yourself to be.

Linux boot time? How about hardware startup!

[Ed Random]

All in all, playing with parallelized OS startup is very nice but the real problem lies elsewhere...

In my experience (data center, 350+ Intel-based servers, Linux + Windows plus a bunch of SPARC Solaris boxes), the OS boot time is negligible compared to the time needed for hardware initialization:

- BIOS startup
- Memory check
- Remote Console init (DRAC/XSCF etc.)
- RAID Controller(s) init, disk spinup
- RAID Consistency Check, volume initialization
- Start Boot Sequence

Especially the disk subsystems cause large delays - most time is spent waiting for the GRUB screen.

Parallelizing the hardware initialization is where we could make some significant progress.