[HACK][HOW-TO] Fix lags w/ ext3 sd partition on STOCK firmware. 6 Aug 2010

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DISCLAIMER
DO IT ON YOUR OWN RISK.
ME OR ANYONE ELSE ON THIS FORUM IS NOT RESPONSIBLE FOR BRICKED/DEAD DEVICES AND/OR DEAD SD CARDS.

YOU SHOULD UNDERSTAND EVERY STEP IN THIS HOW-TO BEFORE ATTEMPTING TO FOLLOW.

INFO
This fix/hack mounts second ext3 partition of your EXTERNAL SD card at startup and binds /data/data and /data/dalvik-cache to it. This will give you ~1400 Quadrant score on the stock ROM with AT&T bloatware.

This fix/hack is based on the anomalous3 info posted here

Originally Posted by anomalous3

An explanation of how this was done:
When looking through the init.rc, I realized that there was only one thing running as root that could safely be replaced; the boot logo player. So, all this does is replace the boot logo player with a script that calls userinit.sh from /data/local and then calls the (now renamed) bootlogo player for those of you who want that nifty startup screen
A super simple (and slightly dirty) hack but I figured it might come in handy for those of us who are impatient and would like to do our own tweaks.

PREREQUISITES
1. This guide was tested on complete STOCK ROM. If you need to revert use Odin3 One-Click Downloader
2. You will need root on your device. [How To] Root
3. Make sure you have latest busybox (I have v1.17.1), search market for "busybox" or use this qrcode:

4. You should have adb working until someone will help me figuring out how to pack in handy update.zip
5. You need sdcard with first partition fat32 and second partition ext3. I use 6.5Gb fat and 1.5Gb ext3 (I never tested, but it was mentioned in Mimocan thread DO NOT CREATE BIGGER THAN 1.9Gb EXT PARTITION)

HOW-TO
Step -1. I strongly advise to Backup your ROM (Use Rom Manager)

Step 1. Download and Unpack attached lagfix.zip
Step 2. Copy into root of Internal sdcard or push files using adb:

adb push playlogos1 /sdcard
adb push userinit.sh /sdcard

Step 3. Backup stock boot logo using adb:

adb pull /system/bin/playlogos1 playlogos1.bak

Step 4. ADB shell to device and became a root

adb shell
$ su
#

Step 5. Remount root filesystem as rw

busybox mount -o remount,rw -t rootfs /

Someone please advise if this step is necessary

Step 6. Rename stock boot logo:

mv /system/bin/playlogos1 /system/bin/playlogosnow

Step 7. Copy playlogos1 and userinit.sh and fix permissions:

cp /sdcard/playlogos1 /system/bin/playlogos1
cp /sdcard/userinit.sh /system/bin/userinit.sh

chmod 755 /system/bin/playlogos1
chmod 755 /system/bin/userinit.sh

Step 8. Remount root filesystem as ro

busybox mount -o remount,ro -t rootfs /

Step 9. Reboot and verify fix:

$ su
# ls /sd-ext
data
dalvik-cache

TROUBLESHOOTING
- If you do not have /sd-ext after reboot - script is not working
- If content of /sd-ext is empty I bet you are using old busybox

REVERT FIX
Note: Due to userinit script, I have to play with it in order to revert script changes. Will do it this weekend.

adb shell
$ su
busybox mount -o remount,rw -t rootfs /
cd /system/bin/
rm playlogos1
mv /system/bin/playlogosnow /system/bin/playlogos1
busybox mount -o remount,ro -t rootfs /

Thanks to everyone involved including, but not limited to: designgears, Koush, anomalous3 and NukaCola

Change log:
06/08/2010 Added revert step
06/08/2010 Initial release

Okay, am i the only person having problems creating partitions for sd on ubuntu everytime i try it says card damaged error.

Gparted boot disk works for me....

Does this script have shutdown scripts in it or no? I guess it is just like the Vibrant script?

Is there also a 130MB limit for apps like in the other fix?

Any other gotchas?

Originally Posted by mykenyc

Okay, am i the only person having problems creating partitions for sd on ubuntu everytime i try it says card damaged error.

Hm... I never did this way but it should work.
Try to do so with ROM Manager:
Choose Partition SD card.
Choose your ext size (I suggest 512Mb)
Choose swap as 0.

Let me know if it works for you.
I used parted to create fat and ext2 and then upgraded to ext3 under ubuntu.

Originally Posted by alphadog00

Does this script have shutdown scripts in it or no? I guess it is just like the Vibrant script?

Is there also a 130MB limit for apps like in the other fix?

Any other gotchas?

All the script do is injects call to userinit and then call usual boot logo player.
userinit provided is from justanothercrowd work or even from app2sd earlier.
It is completely uncanged from the vibrant version and it looks great.
This script is:
1. /sd-ext if needed
2. mounts mmcblk1p2 to it
3. if not here binds /data/data as /sd-ext/data
4. if not here binds /data/dalvik-cacheas /sd-ext/dalvik-cache

magic done.

Also, there is only possible 2gb limit (mentioned in mimocan thread at modaco, I never tried to create more then 2Gb)

Originally Posted by XorZone

All the script do is injects call to userinit and then call usual boot logo player.
userinit provided is from justanothercrowd work or even from app2sd earlier.
It is completely uncanged from the vibrant version and it looks great.
This script is:
1. /sd-ext if needed
2. mounts mmcblk1p2 to it
3. if not here binds /data/data as /sd-ext/data
4. if not here binds /data/dalvik-cacheas /sd-ext/dalvik-cache

magic done.

Also, there is only possible 2gb limit (mentioned in mimocan thread at modaco, I never tried to create more then 2Gb)

I was reading the last page of the vibrant thread, and he mentioned still wanting to add unmount commands and such for shutdown.

I am assuming that there is not mic issue as in the other version?
Has anyone tested yet with real DB IO? The other fix had boosted Quadrant scores, but still had terrible.

Just curious if anyone did any real world tests yet.

Thanks i appreciate everyone work but i give up on this lag fix stuff/gps fix/or antenna issues that's not working for me. I'm just going to get the blackberry torch, and when Samsung update everything or we get more development i will be back. And i will use my second line to buy another captivate. So be back soon my android brothers happy hacking!

Originally Posted by alphadog00

I was reading the last page of the vibrant thread, and he mentioned still wanting to add unmount commands and such for shutdown.

I am assuming that there is not mic issue as in the other version?
Has anyone tested yet with real DB IO? The other fix had boosted Quadrant scores, but still had terrible.

Just curious if anyone did any real world tests yet.

I will update it as soon as they will add more info or update a script.
I didn't and probably will not do any "realworld" testing as I fill it is boosted and better.

It's up to you if to use it.

No mic problems because kernel is stock.

Originally Posted by mykenyc

Thanks i appreciate everyone work but i give up on this lag fix stuff/gps fix/or antenna issues that's not working for me. I'm just going to get the blackberry torch, and when Samsung update everything or we get more development i will be back. And i will use my second line to buy another captivate. So be back soon my android brothers happy hacking!

Well. I do not have any issues with GPS/MIC and lag now.
Pretty happy with the device. Only kernel source problem annoying, but never thought to regret the deal.

It's your decision. Farewell. Take it easy, there are more important things then cell phones