Linux - Make pen drive as RAM

 Linux - Use a USB drive as RAM

Actually I am going to clear it first that it does not increase your RAM memory, the process is used for improved performance by cpu using increased swap space but it works same as increased RAM.

It increases your swap space of the system according to size of your pen drive. Suppose you have given 2GB swap space in your system and now you use 8GB pen drive for increased swap space, it shows total swap space around 10 GB.

Follow the process to increase performance of your system.

First make sure that your pendrive is empty and there is no necessary data in it otherwise it will be lost.
Find the device name of your pendrive using command

fdisk -l

In my case, it is /dev/sdb1
 
Now unmount the pendrive using

sudo umount /dev/sdb1

Create swap partition using

sudo mkswap /dev/sdb1

Make it enabled using

sudo swapon -p 32767 /dev/sdb1

32767 is the priority,  The maximum priority can be 32767 and the lowest 0.

To see if swap space is increased or not, Run following command

cat /proc/swaps

If you need to take the pendrive out, do the safety removal process using

sudo swapoff /dev/sdb1

Now you can remove your pendrive but it will not be detected, you need to format it in fat32 or NTFS (in any familiar partitions)
Now pen drive will not be detected, format it again in fat32 using

mkdosfs -F32 -v -n "" /dev/sdb1/span>

Now pendrive will be detected again.

Note :
Swapping is necessary for two important reasons. 

First, when the system requires more memory than is physically available, the kernel swaps out less used pages and gives memory to the current application (process) that needs the memory immediately. 

Second, a significant number of the pages used by an application during its startup phase may only be used for initialization and then never used again. The system can swap out those pages and free the memory for other applications or even for the disk cache.