[SWAP] Swap on Internal * v0.5 alpha *
SWAP on internal
For the moment, the script is confirmed to work only on ROMs with the chinese x-part (or data2ext) by Atroy script only
Extend your RAM with very quick internal SWAP
(read at the end of this post for alternative).
The only ROM I am aware of using this script out of the box is the excellent MIUI XJ x-part
However, I intend to develop a non-loop based version shortly. It should will be compatible with most ROMs, so stay tuned.
What and Why
I decided to make a script that places the swap file on internal memory. Many people place it on SD card, but to me it seems somewhat pointless, as it hardly offers sufficient performance.
However, placing it on the internal memory makes it a much more interesting concept, because it has much better random read/write performance than even the fastest SD cards.
Warning: placing SWAP on internal memory will subject it to frequent read/write operations which in theory shortens lifespan of internal memory chip which you cannot replace. This is because flash memory has limited number of write/read cycles to it. So, consider yourself warned.
- although true, in reality I have been unable to find any case of this actually affecting anyone's phone. There is very limited amount of data documenting real-life effect of that process, but most likely your device will be long gone before the internal memory will show any signs of wear.
- the script recreates the swap file on each boot using different physical blocks of memory - this means not the same blocks are always used. More on this in 'Do it right' section.
Do It Right
16-32 MB of swap should suffice. If you think you need more, you are probably wrong. NEVER use all available internal space. The larger the proportion difference between swap size and total free space on the internal data partition, the more breathing space your internal memory gets, as this allows the swap file to be moved around upon every reboot, which, in turn, will make it use the same blocks more rarely, and thus extending memory chip lifespan.
Get rid of bloat you don't use from the system partition, ie: ringtones, live wallpapers, useless system apps. Then create a custom
hboot with smaller system partition and larger data partition. You can do it using this
(also attached to this post).
Play around with swappiness parameter. Still, the default set by the script should serve you well. But if you are paranoid, you can use it to further decrease how often system will write to swap.
Disable execution flag on the scipt in /system/etc/init.d and delete swap.img from internal data directory (on x-part scripts it is /mnt/asec/mtddata/ )
x-part Impacted script (80% chance of rendering your ROM unbootable)
* first public release
* loop device version only
I attached a data2ext script which should offer better performance and battery life than some other a2sd scripts.
You are free to try and flash it on your ROM, but there is a good chance it won't boot any more
- this is a very alpha version and I am not working on it at the moment.
Do not post complaints about it here.
I only want to hear from you if it works!