if you have no swap in your installation this is what you do??? Why???
- Date: Sun, 09 Apr 2017 14:58:00 +0000
- From: GiaThnYgeia <GiaThnYgeia@xxxxxxxxxxxxxxx>
- Subject: if you have no swap in your installation this is what you do??? Why???
A while ago while Thomas Schmitt was helping me with dd and xorriso in
backing up systems and partitions into usb and back the issue of not
having a swap partition in my system came up, since I chose not to
during the installation, and how to create one, lead me into a search of
doing just that.
In the page
there are instructions that I believe work just as well on Debian to
either create a new partition for swap or create a swap file, which I
did not know it was an option.
I chose the second as my partitioning has become complex and most of the
drive is not available during boot-up. So I assume it would run to an
error if I did this on a partition that is not available during boot.
Below you will find the exact instructions I used and worked fine for me
on Stretch (I believe to be true for all Debian).
But here come some questions:
1 What is the difference functionally of having a swap partition from
having a swap file? Is it that you can use a separate physical disk
that will take the wear and tear of swaping?
2 Is swap size relevant to ram, should it be equal, greater, smaller?
Advantages disadvantages? I rarely see in a workstation and my/our use
anywhere close to 4GB being used, it usually maxes out around 2,5GB. No,
no killing games here, maybe some chess and gnubg. Is it that a Ram of
1GB would benefit from 2-4GB swap space while with 16GB or Ram swap
would never be used?
3 chmod 600 for the swapfile. Why?
4 Is "dd bs=1M count=4M" that defines the 4,000Mb of space/size of the file?
I am now going to use gnubg to test my mem capabilities. I think making
it calculate best move 4-5 moves ahead in bg or chess will stress the
system out :)
# Create an empty file (1K * 4M = 4 GiB)
sudo mkdir -v /var/cache/swap
sudo dd if=/dev/zero of=swapfile bs=1K count=4M
sudo chmod 600 swapfile
# Convert newly created file into a swap space file.
sudo mkswap swapfile
# Enable file for paging and swapping.
sudo swapon swapfile
# Verify by: swapon -s or top:
top -bn1 | grep -i swap
# KiB Swap: 4194300 total, 4194300 free
# To disable, use
sudo swapoff swapfile.
# Add it into fstab file to make it persistent on the next system
echo "/var/cache/swap/swapfile none swap sw 0 0" | sudo tee -a
# Re-test swap file on startup by:
sudo swapoff swapfile
sudo swapon -va
"The most violent element in society is ignorance" rEG