increase boot speed in multiple core processor

[kapil]

i have amd 64x2 processor. i came across this article:

9) Increase the start speed of multi-core CPU systems.

This will slow down systems that have a single CPU. For multi core CPUs, we can change the services to all start together (in parallel) during boot time. The command to do this is;

sudo perl -i -pe 's/CONCURRENCY=none/CONCURRENCY=shell/' /etc/init.d/rc

and then reboot with

sudo shutdown -r now

Read more: http://ubuntulinuxhelp.com/10-things...#ixzz0y7P5dkCD

i am bit skeptical. has anyone tried it? is there any way to undo these changes?

[Snowhog]

Re: increase boot speed in multiple core processor

The /etc/init.d/rc file is what is being changed. As root, just make a backup copy first.

[SIR_Taco]

Re: increase boot speed in multiple core processor

Snowhog beat me to it as I was typing

But, if you open the /etc/init.d/rc file.... here is the warning:

# Specify method used to enable concurrent init.d scripts.
# Valid options are 'none', 'startpar' and 'makefile'. To enable
# the concurrent boot option, the init.d script order must allow for
# concurrency. This is not the case with the default boot sequence in
# Debian as of 2008-01-20. Before enabling concurrency, one need to
# check the sequence values of all boot scripts, and make sure only
# scripts that can be started in parallel have the same sequence
# number, and that a scripts dependencies have a earlier sequence
# number. See the insserv package for a away to reorder the boot
# automatically to allow this.
CONCURRENCY=none

Honestly, unless you have some odd things starting up when you boot, there should be no problem.

I hadn't even considered this before since the latest releases (10.04 and 10.10 alphas) boot pretty darn quick anyway. But maybe I'll give it a shot to see if there's a decent improvement with my 4 cores.

I'll let you know how it goes.

[Snowhog]

Re: increase boot speed in multiple core processor

Tried with the tweek, and again without. I didn't see any real noticeable decrease in the time from kernel selection (Grub Menu) to the loading of the Desktop. Both were timed at just over 40 seconds. I only have a dual-core Intel CPU. I went back to the original configuration.

[SIR_Taco]

Re: increase boot speed in multiple core processor

I tried it with the 'startpar' option mentioned in the /etc/init.d/rc file and it shaved maybe 5 seconds off (from grub to KDM login) according to dmesg anyway. I'm around 11-12 seconds now. I didn't try the 'shell' option mentioned in the link provided, but seeing as how it's from June 15th 2009 it's quite likely they have changed the option from 'shell' to 'startpar'.

If you had a bunch of time on your hands you could probably sit down and figure out what can be moved up or down the boot order to squeeze a little more time out of it. But I'm not that ambitious about my boot time

[GreyGeek]

Re: increase boot speed in multiple core processor

Where did you get "startpar". It's not in my 93 repositories.

[SIR_Taco]

Re: increase boot speed in multiple core processor

If you edit rc file (sudo nano /etc/init.d/rc) and go to line 23, it should state the text I quoted before.

On line 33 you should find "CONCURRENCY=none", I changed it to "CONCURRENCY=startpar" which I assume means "start parallel"

[Snowhog]

Re: increase boot speed in multiple core processor

Where did you get "startpar". It's not in my 93 repositories.

It's not a package - it's an option for the:

sudo perl -i -pe 's/CONCURRENCY=none/CONCURRENCY=shell/' /etc/init.d/rc

so it would then be:

sudo perl -i -pe 's/CONCURRENCY=none/CONCURRENCY=startpar/' /etc/init.d/rc

At least, that's how I read SIR_Taco's post.

[GreyGeek]

Re: increase boot speed in multiple core processor

The rc file also has this statement:

# Check if we are able to use make like booting. It require the
# insserv package to be enabled. Boot concurrency also requires
# startpar to be installed.

Documentation sometimes misleads ....

Did you have to change the order of the naming of any of those startup files?

[SIR_Taco]

Re: increase boot speed in multiple core processor

GreyGeek:
No, I didn't have to change the order of the startup files. And I don't seem to have the "requires startpar to be installed" part in my rc file either.

The issue that they're warning about is that you could, possibly, have a service start before it's dependencies are met.

For instance.... you could have your wireless network trying to authenticate before network-manager is loaded. Or anything else you can think of. You can't drink your milk if it hasn't been poured yet

EDIT:

Having said that.... that doesn't mean that you wont run into troubles. Make a backup to be safe.

[GreyGeek]

Re: increase boot speed in multiple core processor

Using startpar didn't cause any troubles, but it didn't make any difference is boot up speed, either. Not that I could tell, +- a couple seconds.

[kapil]

Re: increase boot speed in multiple core processor

Using startpar didn't cause any troubles, but it didn't make any difference is boot up speed, either. Not that I could tell, +- a couple seconds.

+1

undid the changes. thanks for suggesting backup of that file

[Yuri sss]

Re: increase boot speed in multiple core processor

Might as well give it a try for my 4-core Phenom II

edit:
Applied it now and didn't have any problems booting. Seems a bit faster, too