What Is zRAM/Swap?
How to Enable zRAM / Swap in Any Custom Rom – MT65XX. zRAM is a Linux kernel function that gives a form of virtual memory compression. zRAM increases overall performance by way of keeping off paging to disk and the usage of a compressed block device in RAM instead, inside which paging takes area until it is essential to apply the swap area on a hard disk drive. since using zRAM is an alternative way to provide swapping on RAM, zRAM allows Linux to make a better use of RAM when swapping/paging is needed, specifically on older Devices with much less RAM installed.
Requirements :- 
  • PC
  • Text Editor :-  CLICK HERE
  • tiny*** files :- CLICK HERE
  • Knowledge about unpacking and repacking boot.img
Procedure :- 
1. Download these 4 tiny*** files :- CLICK HERE and Extract it you will get following 4 files listed below-
tiny_mkswap
tiny_swapoff
tiny_swapon
tiny_switch
2. Now Copy these files and paste in a Folder.
3. Extract the Rom(in which do you want to enable swap or zram)
4. Now go to System – Bin folder and paste those four files here (all tiny** files)
5. Unpack the boot.img and go to initrd or Ramdisk folder :-
6. See if there is any enableswap.sh file?
7. If yes, then NO need to do or edit anything in boot.im
8. If no, Download this zip file :- CLICK HERE
9. You will see these two following files listed Below :
  • enableswap.sh
  • init.rc file
10. Now copy enableswap.sh and paste in ramdisk folder.

Now open init.rc file you've downloaded in step 9 and copy all Lines –

1. If your rom is Kitkat/Kitkat based (4.4.x) :- 
  • Open init.rc (in ramdisk) with Notepad++ and paste in bottom. and Save it.
  • Repack the boot.img and replace it with your existing boot.img.
  • Zip the Rom And Flash it

2. If your Rom is Lollipop/Lollipop Based (5.x.x) :-
  • Open init.mt65xx.rc (in ramdisk) with Notepad++ and paste in bottom and Save it.
  • Repack the boot.img and replace it with your existing boot.img..zip the Rom And Flash it

3. your rom is Marshmallow or Nougat (6.x.x or 7.x.x) :- 
  • Open init.mt65xx_common.rc (in ramdisk or initrd folder) with Notepad++ and paste in bottom and Save it( if init.mt65xx_common.rc is not available, Paste it in init.mt65xx.rc)
  • Repack the boot.img and replace it with your existing boot.img..zip the Rom And Flash it

Note:- Using This Guide You can enable only 512MB zRam
If you have any queries about this guide, comment below.

Screenshot :-