If you're using Pre and meta-doctored it to #webOS 2.1.0 like I did, you should install and using Govnah + custom kernel (UberKernel). And then, since Pre only has 256 MB of memory, you can tweak the compcache (from Linux compcache that already porting to custom kernel by webos-internals) to make the value changed from only 10 MB to 32 MB, so the performance will enhance.

I tend to make it permanent, so here's what I did:
1. Connect Pre using USB cable to your PC
2. Accessing linux:
$ novaterm
3. Type following command:
# /usr/sbin/rootfs_open -t
# vi /etc/event.d/compcache
4. Change the value:
Look for value 10240 in line 10, then replace it with 32768, save and quit (:wq)
5. Reboot the device:
# /sbin/reboot

After it rebooted, you can check the compcache value using Govnah. For complete how-to, you can check here.