adding swap volume

Question

I have recently installed ubuntu 12.04 alongside my windows 7. But i did not created swap volume for ubuntu. There are already 4 partitions on my hard drive ( one windows 7 , one system tools ( windows 7), one for ubuntu and one for common media storage(ntfs)). Therefore Gparted didn't allow me to create any further partition for swap volume.All it said to create an extended partition, but i do not know to do this. I want to create a swap volume out of common media storage. How can i accomplish this?

And I'm completely new at Ubuntu , so can you suggest some good getting started tutorial for it?

Solution

To create a fifth partition, you would have to remove one of your four existing primary partitions, create an extended partition (which is a container for logical partitions, so you can effectively have more than four partitions on a system with an MS-DOS type partition table), and recreate the partition you'd deleted as a logical partition inside the extended partition. You'd have to have somewhere to back up the partition you remove (or at least its contents). This is a big hassle, in some instances prohibitively so.

Therefore, unless you need your Ubuntu system to support hibernation (which requires a swap partition), you should set it up to use a swap file instead. This performs just as well (provided your swap file is stored on an ext2, ext3, or ext4 partition, which it would be).

The following instructions are taken from the Swap FAQ in Ubuntu's community documentation. It is not an exact quote, since I have changed the formatting for internal consistency and for compatibility with AskUbuntu; I have also made a few tiny edits for clarity. This documentation is licensed under CC-BY-SA, which permits inclusion (with or without modification) into articles like this (which, as AskUbuntu.com content, is also made available under that license). It might make sense to edit this further for clarity (or other purposes), but if significant further modifications are made, it would be good to explicitly offer them for consideration "upstream" (so as to improve the original source also).

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Four-step Process to Add Swap File

• Creating a file the size you want.
• Formatting that file to create a swapping device.
• Adding the swap to the running system.
• Making the change permanent.

INFO: This will not work on btrfs-filesystems at the moment. See man swapon.

Instructions For Adding a 512 MiB Swap

1. Create a file 512 MiB size (or replace what with whatever size you want):

   We will create a /mnt/512MiB.swap swap file and set the permissions so that users cannot read it directly.

   sudo fallocate -l 512m /mnt/512MiB.swap
   sudo chmod 600 /mnt/512MiB.swap
   

   fallocate length suffixes are: k, m, g, t, p, e (See man fallocate.)

   By default your swap file may be created world readable. We set the 600 mode permissions in order to prevent users from being able to read potentially sensitive information from the swap file.

   If fallocate fails with fallocate failed: Operation not supported as it currently does on my Maverick machine, you can do this the old way, again 512 MiB:

   sudo dd if=/dev/zero of=/mnt/512MiB.swap bs=1024 count=524288
   sudo chmod 600 /mnt/512MiB.swap
   

2. Format that file to create a swapping device:

   sudo mkswap /mnt/512MiB.swap
   

3. Add the swap to the running system:

   sudo swapon /mnt/512MiB.swap
   

   The additional swap is now available and can be seen by cat /proc/meminfo.

4. Making the change permanent:

   Edit /etc/fstab:

   gksudo gedit /etc/fstab
   

   Add this line at the end of the file:

   /mnt/512MiB.swap  none  swap  sw  0 0
   

   Save. After the next reboot the swap will be used automatically.

Example of making a swap file

This is an example of making and using a swap file on a computer with no swap partition.

user@computer:~$ sudo fallocate -l 512m /mnt/512MiB.swap
Password:

user@computer:~$ sudo mkswap /mnt/512MiB.swap
Setting up swapspace version 1, size = 536866 kB
no label, UUID=dd6a01c8-93f0-41e0-9b7a-306956d8821b
user@computer:~$ sudo swapon /mnt/512MiB.swap
user@computer:~$ cat /proc/meminfo
MemTotal:       499496 kB
MemFree:          9156 kB
Buffers:          4748 kB
Cached:         233140 kB
SwapCached:        724 kB
Active:         254432 kB
Inactive:       157920 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:       499496 kB
LowFree:          9156 kB
SwapTotal:      524280 kB
SwapFree:       523556 kB
Dirty:             128 kB
Writeback:           0 kB
Mapped:         243420 kB
Slab:            20672 kB
CommitLimit:    774028 kB
Committed_AS:   648680 kB
PageTables:       2224 kB
VmallocTotal:   524280 kB
VmallocUsed:      5708 kB
VmallocChunk:   518176 kB
user@computer:~$ gksudo gedit /etc/fstab
user@computer:~$ free
             total       used       free     shared    buffers     cached
Mem:        499496     479488      20008          0       8256     215892
-/+ buffers/cache:     255340     244156
Swap:       524280       3856     520424
#####Then, after running a few more programs...
user@computer:~$ free
             total       used       free     shared    buffers     cached
Mem:        499496     492768       6728          0       1240     142336
-/+ buffers/cache:     349192     150304
Swap:       524280      53384     470896

#####Next, reboot to make sure it will work consistently.
user@computer:~$ free
             total       used       free     shared    buffers     cached
Mem:        499496     493136       6360          0       7528     174700
-/+ buffers/cache:     310908     188588
Swap:       524280      17148     507132

Undoing Your Changes

Undoing basically follows the same process in reverse.

gksudo gedit /etc/fstab

Remove the line:

/mnt/512MiB.swap  none  swap  sw  0 0

Remove the swap from the running system and remove the swap file:

sudo swapoff /mnt/512MiB.swap && sudo rm /mnt/512MiB.swap

No need to reboot.

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Source: As described above in detail, this is a derivative work of SwapFaq in the Ubuntu community-authored documentation. That page is written by Contributors to the Ubuntu documentation wiki. (Maintainers of this AskUbuntu answer should carefully read this legal information before editing or removing this citation, to ensure that the requirement to give credit to the original authors continues to be met.)

Comments

[Mhmd Korhani]

thnx for your help!

[CMCDragonkai]

Why would this fallocate failed: Operation not supported happen? Is it a bug? I know that fallocate is available, but what causes such an error?