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Posts: 549 | Thanked: 502 times | Joined on Feb 2008 @ Bowling Green Ohio (united states)
#1
The purpose of this thread is to provide as much information on boosting performence in deblet as possible.

This will cover:
* General boot up time
* Application start up speed
* Application responsivness
* Fix system clock error



NOTICE:
Most of what is provided here has only been tested on my N800 running Deblet with 400MB of swap on a 3.4GB partition and i am not responsible for what you do to your tablet if things go wrong.

All of the steps provided are optional and may have verrying effects on your tablet depending on your set up.


Step 1 ~ speed up boot prosess with insserv

What we are going to do first is enable parallel booting, (backgrounding), ware one service at boot time doesn't delay other faster services that don't depend on it.

Basicly, what slows down system boot time is init scripts starting, stoping and, re-starting. This is because the init scripts don't conform with LSB's dependency based order, witch is what the scripts depend on.

Do the following as root in a terminal:

Code:
apt-get install insserv
Code:
echo 'CONCURRENCY=shell' >> /etc/default/rcS
What this will do is re-order the init script setup to conform to LSB and also allow parallel startup.



Step 2 ~ Application start up speed with preload

Comonly, the way the system boots with responsivness is to cache it's information. When the system boots up it caches files/binarys that your likely to use to RAM. Similar to "upper memory" in Windows.

However, preload is designed for user applications and depending on weather you are using swap or not, may not have eny effect on your boot up speed, or even slow down boot up speed.

The primary function of preload is to run as a daemon and monitor or "learn" about what applications you use and over time will adapt the system's caching system to focus on only what you want to do with your system thus over time your system (shuld) start to see a noticeable difference with overall speed.

Again, as root do the following:

Code:
apt-get install preload


step 3 ~ Application responsivness

By defult, the kernel swaps data and applications to the rootfs in order to free ram. However since we don't have a lot of ram available on our system so this feature is verry important in order for deblet to run smothly. However the defult setting for this feature is 60, however, to reserve ram we will set this to 80.

As root do the following:

Code:
echo 'vm.swappiness=80' >> /etc/sysctl.conf
^^ Swappiness is the ammount of virtual memory (swap partition) your computer is ordered to use.

Note: on a regular computer this would be the exact oppeset, however since there is only a comparably small amount of ram on our tablets we need to conserve as much as we can.

The second part of this setup is to change how the kernel frees caches of block devices vs filesystem entries. To make applications more responsive we would perfer that the kernel tries to free up cashe by getting rid of cached block devices before cached filesystem entries because getting rid of cached filesystem entries makes our filemanagers and browsers more responsive.

To enhance this function type the following as root:

Code:
echo 'vm.vfs_cache_pressure=50' >> /etc/sysctl.conf


step 4 ~ fix system clock

As you have noticed, the system clock often fails to set it's self, this is due to a unset parameter in /etc/init.d/hwclock.sh and hwclockfirst.sh.

As root, make a backup of the original files, in case something gos wrong:

Code:
cd /etc/init.d/
cp hwclock.sh hwclock.sh.bak
cp hwclockfirst.sh hwclockfirst.sh.bak
And edit the settings of /etc/init.d/hwclock.sh and hwclockfirst.sh to look like this:

Code:
HWCLOCKPARS="--directisa"



Links:

http://sidux.com/PNphpBB2-viewtopic-...-tweaking.html
http://packages.debian.org/lenny/preload
http://www.techthrob.com/tech/preload_files/preload.pdf
http://www.cyberciti.biz/tips/speed-...ux-system.html
http://packages.debian.org/lenny/readahead
http://wiki.debian.org/BootProcessSp...process - blog
http://initscripts-ng.alioth.debian....ootcharts.html
http://wiki.debian.org/LSBInitScript...dencyBasedBoot
http://packages.debian.org/lenny/insserv
http://forums.debian.net/viewtopic.p...r=asc&start=15
http://forums.debian.net/viewtopic.php?t=14129


If you have eny questions, find a flaw, need help, or would like to add something to the list, fell free to let me know and i will gladly respond.
__________________
I'm an advanced user and a bit of a modder.
----------------------------------------------
I am involved with Mer, Deblet, and NITdroid.
My ports/creations/hacks: GNOME (for Deblet), Cdeb2», Ubuntu, playable flash games in the "Get Started" app, DBS, ect...


enhanced fedora port has been canceled in favor of NITDebian (TBA)

Last edited by b-man; 2008-11-18 at 02:55.
 

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