By default, System Restore uses 12% of your drive's disk space, but you can adjust it to make it bigger or smaller by moving the slider to the left to make it smaller. You can set System Restore to use only 1 gig space which just means not many restore points will be saved.
See attach image:
>>>"i mean can i save the restore point of C:\ in my external hard drive,"
No, that would not work, System Restore only uses the System volume Information folder in each monitored partition to store its restore points. You can't have System Restore monitored C:\ and then move or save the contents of the C:\ SVI folder into an external drive, it won't work.
Further more, it's also not a good idea to have System Restore monitored an external drive because if changes are made while it's not connected to the system, the next time it's connected, SR will find inconsistency in the SR log and caused restore points to become corrupt.
>>>"and i feel like if any file i added to my hard drive it copied itself in System Volume Information automatically!!
Not all files you added into your harddrive copied itself into the System volume information, only the monitored files, registry settings etc are stored in that folder(the snapshots of system changes).
System Restore is not the same as any backup software like Acronis True Image or Norton Ghost. System Restore does not backup all your data in the system.
It only monitors certain files and registry settings, it only monitors and save system changes so you can go back to the previous state if something happens.
It is not a replacement for any backup software.
The System volume information files can get too large depending on the size of the drive and how many restore points are stored, and if Indexing Service is turned on, it also stores files in there.
If you don't want System Restore to use a big space then adjust the disk space used by System Restore, e.g., set it to 1 gig only.
I would not recommend disabling System Restore totally for good as you may just need it oneday, I have used it many times already.
