Originally Posted by nijinashok00
By default Linux doesn't allows to increase or decrease / memory because it is a primary partition. Using 3rd party software may cause lose of data. So it is better to create new partitions with your available free memory. For example you can create a new partition for a directory which utilizes more memory using fdisk utility. If you wish to increase or decrease the partition memory use logical volume.
Actually you cannot perform partition operations on any file system that's 'on-line' or mounted. So to resize the partition that's being used as the root of your OS, you would have to boot into a different OS (like a LiveCD) so that you can make adjustements to that partition.
The best set up for that would of course be to have a partition available right after the "/" partition that you could simply delete, and then 'grow' the partition you need more space for. Of course this is not always possible as some people have extended partitions (which are just basically big containers for other partitions) that are positioned just after the root partition on the drive. You may end up having to delete the extended partition and all the other partitions that it contains just so you can make space to 'grow' your root drive.
Now this may be considered a workaround to the situation, but you can also regain space by performing what's called symbolic linking. You could physically move files and folders from your "/" partition onto another partition, thus regaining space in your root partition. Then you can create a symbolic link to the folder you moved over. Provided that the filesystem is the same type and is auto-mounted on boot, you shouldnt have problems. I would recommend, of course, moving non-system files to a new partition (like maybe your pictures, movies, music, etc) just so that your system still boots even if the symlink goes down (and it normally shouldnt, but its always good to be prepared).