There is nothing wrong with the stock dxjpe. It must be something you have installed after flash that is killing it.  It's usually some taskiller app which is the problem.

---

Added on July 11, 2011, 12:34 pm
I'm using dip's rom and kernel at the moment and it's good. The installation steps are on his thread's first page, at the bottom. I'm pasting it below:
Installation

(before you install make a backup of data titanium).

Standart - JQ1/ZUJP8/DXJPD/DXJPE
Custom rom - example overcome

0. (Backup app/data - titanium)

1. Install standart firmware JQ1 or ZUJP8 or DXJPD or DXJPE (here http://www.samfirmware.com/WEBPROTECT-p1000.htm)

2. Install my kernel http://forum.xda-developers.com/show...62&postcount=2 for root and ClockworkMod Recovery.

3. Install my custom firmware (GT-P1000_DXJPE_by_DiP7_v2.2.3)
(ClockworkMod Recovery -> install zip from sdcard -> choose zip from sdcard).
Since you're already on stock DXJPD, use odin to flash dip's kernel . Download and use the TAR version ie click the "PDA" section and select the Tar file. And click Start.
To flash the rom, go into recovery mode etc.

If you don't know how to use odin app and recovery to flash kernels/roms ,you'll need to go to youtube to find some video tutorial.

There is nothing wrong with the stock dxjpe. It must be something you have installed after flash that is killing it.  It's usually some taskiller app which is the problem.

---

Added on July 11, 2011, 12:34 pm
I'm using dip's rom and kernel at the moment and it's good. The installation steps are on his thread's first page, at the bottom. I'm pasting it below:
Installation

(before you install make a backup of data titanium).

Standart - JQ1/ZUJP8/DXJPD/DXJPE
Custom rom - example overcome

0. (Backup app/data - titanium)

1. Install standart firmware JQ1 or ZUJP8 or DXJPD or DXJPE (here http://www.samfirmware.com/WEBPROTECT-p1000.htm)

2. Install my kernel http://forum.xda-developers.com/show...62&postcount=2 for root and ClockworkMod Recovery.

3. Install my custom firmware (GT-P1000_DXJPE_by_DiP7_v2.2.3)
(ClockworkMod Recovery -> install zip from sdcard -> choose zip from sdcard).
Since you're already on stock DXJPD, use odin to flash dip's kernel . Download and use the TAR version ie click the "PDA" section and select the Tar file. And click Start.
To flash the rom, go into recovery mode etc.

If you don't know how to use odin app and recovery to flash kernels/roms ,you'll need to go to youtube to find some video tutorial.

This is the step if you want gingerbread DXJPI.

1.Your tab must be stock ROM. I suggest you read the first post how to revert to stock ROM and using samsung KIES.
There is a link to multi-upload to first page and using ODIN flash that ROM. You will get stock froyo.
2. Root your tab as per instructed in first page on rooting froyo , and install bootloader patch apk 1.0.0
3. Apply bootloader patch, after that uninstall that program.Because later this bootloader will conflict with gingerbread DXJPI.on gingerbread there no need bootloader cause samsung didn't put in.
4. Run samsung Kies on your Pc, make sure you get latest version install, (click help and check update).
5.Connect you tab to your Pc and you should get notification update to stock DXJPI  phone DXJPE cse DXJPH
6. Depend on your speed. Prefer TM UNIFIED cause is take time to download. usually PITA.
7.now after your tab in DXJPI, i strong suggest you take a hard reset, cause you sure you tab is fresh from anything (dalvik cache clean). refer post 1 how to use samsung dial code to hard(factory reset)
8.Root your tab on gingerbread . Refer 1 page complete with link page tutorial how to root your tab on gingerbread
9. Download DIP7 kernel, refer xda developer ,android development site.DIP7  ROM on DXJPI GINGERBREAD.
10.Download DIP7 ROM , refer xda developer galaxy tab android development under DIP7 ROM
11.Flash DIP7 kernel using CMW3 and using recovery mode, apply DIP7 ROM from SD card.
12. Now your wish come through with magical moment.Your tab is blazing fast.You get honeycomb graphic boot-up image.Don't forget to convert to EXT 4 . You get fast and furious machine now.I,m tell you,way-way better virtual machine.
You will be proud because this DXJPI only exclusive and privilege on Malaysia only (I don't know about other country) but as far i'm know other country scream for this version.If you look at samfirmware  , there is no GINGERBREAD DXJPI version.So people may be difficult to get .(must google to download).
So enjoy your tab. Don't worry .A lot  of forumer will help you along the way.

Answer yes,you can use ODIN 1.7 to update to stock gingerbread DXJPI  PHONE DXJPE CSC DXJPH.
DIP7 ROM base on gingerbread DXJPI , Refer xda, galaxy tab android development under DIP7 ROM and kernel.
Once your tab in DXJPI than you root your tab ,just follow the guide,ok.

Answer yes,you can use ODIN 1.7 to update to stock gingerbread DXJPI  PHONE DXJPE CSC DXJPH.
DIP7 ROM base on gingerbread DXJPI , Refer xda, galaxy tab android development under DIP7 ROM and kernel.
Once your tab in DXJPI than you root your tab ,just follow the guide,ok.

yup... definitely different speed with ext4 its like old win system... from 16 bit to 32 bit...