Dont have swap enough ... make a swap file

[jemadux]

The trick is to make a file and then tell the swapon program to use it. Here’s how to create, for example, a 64
megs swap file on your root partition (of course make sure you have at least 64 megs free):

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dd if=/dev/zero of=/swapfile bs=1024

This will make a 64 megs (about 67 millions bytes) file on your hard drive. You now need to initialize it:

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mkswap /swapfile 65536
sync

And you can then add it to your swap pool:
swapon /swapfile
With that you have 64 megs of swap added. Don’t forget to add the swapon command to your startup files so
the command will be repeated at each reboot.

[dedanna1029]

[jemadux]

i found that at one old book ....

[viking60]

Keep it coming - we love old books

[jemadux]

ok viking .... i will post more tips !!

[dedanna1029]

Keep it coming - we love old books

ok viking .... i will post more tips !!

Please do!

[viking60]

I just made a swapfile on my raspberry pi (it has 512 M standard memory -).
As we have learned we can make both a swapfile or a separate partition for swap.

What you choose will not matter in terms of speed or efficiency so you can simply pick what you like.

BUT I chose a slightly different method than our friend above:

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fallocate -l 1024M /swapfile

This will create the directory swapfile and it is set to hold 1024 M in this case.

I could have done it like this:

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dd if=/dev/zero of=/swapfile bs=1M count=1024

..but I didn't

Then I chmoded it:

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chmod 600 /swapfile

- yes it has to be 600

Now it was time to format this to swap:

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mkswap /swapfile

And finally to activate the entire enchilada:

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swapon /swapfile

Just one tip - since you probably will boot into the "home" of root on Raspberry pi you must make sure that you get to /.

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cd /

If not - the last step will not work

You can check it out with Top.

To make it stick after a reboot we need to edit /etc/fstab and add this line:

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/swapfile none swap defaults 0 0


(I will be doing a write-up of my Raspberry pi installation as soon as I understand what I am doing ....so sit tight... )

[viking60]

Just to be clear:
If you have a swap partition and need more swap space; you can use the swapfile in addition to the existing swap partition.
I had set my swap partition to 16 MB and I have 6G of memory so I originally almost figured I did not need swap.

After having installed Steam glances reported that all the swap was constantly full so I decided to add a 2G swapfile.

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sudo fallocate -l 2G /swapfile

And did the rest of the above and added it to /etc/fstab beneath the swap partition:

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.....
# /dev/sda7
UUID=23a0dd5a-40b5-4c94-a583-8e278b0f7491       swap    swap    sw      0       0
# /swapfile This is what I added no /dev no UUID only /swapfile
/swapfile                                       none    swap    sw      0       0


That sure beats trying to drag the swap partition bigger with gparted.

And if you regret it you can easily remove the swap file like this (as root):

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swapoff -a

or

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swapoff /swapfile

If you use the latter then the swap partition you may have will remain.
then

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rm -f /swapfile

[viking60]

Hey we have inspired others too.

https://forum.manjaro.org/index.php?topic=25541.0

All one great big Linux community - I tell you

[dedanna1029]

Good job! It will be inspiring this kid too, once I can finally get a wireless connection.

[viking60]

Here I have recorded a terminal sessions that shows the difference between swapoff -a and swapoff /swapfile.
It shows that I have both a swap partition of 15 MB and a swapfile of 2G. I can turn on/off both.

In addition I show that I can turn off only the swapfile leaving the 15 MB swap partition.


http://showterm.io/f4aa7926e0674827e86d3

[dedanna1029]

Here I have recorded a terminal sessions that shows the difference between swapoff -a and swapoff /swapfile.
It shows that I have both a swap partition of 15 MB and a swapfile of 2G. I can turn on/off both.

In addition I show that I can turn off only the swapfile leaving the 15 MB swap partition.


http://showterm.io/f4aa7926e0674827e86d3

This is SO COOL. I was going to ask how you put it in the container for it there, but I see how now in the code.
You present so much cool stuff to us. Many kudos.

Thank you!