Supposed Ubuntu Speedups - Concurrency=shell, readahead profile
Wednesday, December 31, 2008
After seeing Lifehacker blog about a number of Ubuntu speedups, I decided to test some of them to see their actual effectiveness.
The test machine was a Lenovo T61 with a Core 2 Duo T7500 @ 2.2 ghz and 3GB RAM. All boot times are from the grub menu (started when I pressed enter to start the boot) to the appearance of the login screen. I started with a completely fresh installation of Ubuntu 8.10 which I updated and rebooted 3 times. The default settings are "concurrency=none" in /etc/init.d/rc, but I'm unsure of the default readahead settings. It's possible Ubuntu tries to create a profile after installation, but I have no proof of that, so I assume there is no profile.
The results:
- No modifications (concurrency=none, no readahead profile) - 29.8 sec
- Concurrency=shell, no readahead profile - 29.2 sec
- Concurrency=shell, readahead profile - 28.7 sec
- Concurrency=none, rebuilt readahead profile - 29.2 sec
Here is my full action log:
- Install 8.10
- Update
- Restart x 2
- Restart, timed boot - 30.0 sec
- Restart, timed boot - 29.6 sec
- Set concurrency=shell in /etc/init.d/rc
- Restart, timed boot - 29.9 sec
- Restart, timed boot - 29.1 sec
- Restart, added "profile" to end of grub line
- Timed boot for profile creation - 1 min, 27.7 sec (This is normal)
- Restart, timed boot - 28.7 sec
- Restart, timed boot - 27.9 sec
- Restart, timed boot - 29.6 sec
- Set concurrency=none in /etc/init.d/rc
- Restart, added "profile" to end of grub line
- Timed boot for profile creation - 1 min, 29.1 sec (This is normal)
- Restart, timed boot - 29.3 sec
- Restart, timed boot - 29.1 sec
2 comments:
Yeah, like the lubrication from the wet ink is gonna speed up the boot??? Get real - everyone know that since kernel 2.4.x ink has ZERO effect on i/o blocking.
Your methodology leaves a lot to be desired matey!
Try installing Bootchart (sudo apt-get install bootchart) to get a nice consistent measurement of what you want here for a start, then perhaps consider that the 1.1 second improvement is roughly a 3.7%, which isn't TOO shabby.
That being said, yes there are a lot of faster ways to speed up the boot out there (check out www.moblin.org).