{"id":87,"date":"2022-03-28T21:00:53","date_gmt":"2022-03-29T01:00:53","guid":{"rendered":"http:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/?p=87"},"modified":"2024-10-11T09:32:59","modified_gmt":"2024-10-11T13:32:59","slug":"create-a-linux-swap-file","status":"publish","type":"post","link":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/?p=87","title":{"rendered":"create a linux swap file"},"content":{"rendered":"\n

How to add Swap File<\/strong>
Follow these steps to add 1GB of swap to your server. If you want to add 2GB instead of 1 GB, replace 1G with 2G.
\u00a0 \u00a0 Create a file that will be used for swap:
\u00a0 \u00a0 sudo fallocate -l 1G \/swapfile
\u00a0 \u00a0 If fallocate is not installed or if you get an error message saying fallocate failed: Operation not supported then you can use the following command to create the swap file:
\u00a0 \u00a0 sudo dd if=\/dev\/zero of=\/swapfile bs=1024 count=1048576
\u00a0 \u00a0 Only the root user should be able to write and read the swap file. To set the correct permissions type:
\u00a0 \u00a0 sudo chmod 600 \/swapfile
\u00a0 \u00a0 Use the mkswap utility to set up the file as Linux swap area:
\u00a0 \u00a0 sudo mkswap \/swapfile
\u00a0 \u00a0 Enable the swap with the following command:
\u00a0 \u00a0 sudo swapon \/swapfile
\u00a0 \u00a0 To make the change permanent open the \/etc\/fstab file and append the following line:\u00a0 \u00a0 \/etc\/fstab
\u00a0 \u00a0 \/swapfile swap swap defaults 0 0
\u00a0 \u00a0 Copy
\u00a0 \u00a0 To verify that the swap is active, use either the swapon or the free command as shown below:
\u00a0 \u00a0 sudo swapon –show
\u00a0 \u00a0 NAME TYPE SIZE USED PRIO\u00a0 \u00a0 \/swapfile file 1024M 507.4M -1
\u00a0 \u00a0 sudo free -h
\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 total used free shared buff\/cache available \u00a0 \u00a0 Mem: 488M 158M 83M 2.3M 246M 217M \u00a0 \u00a0 Swap: 1.0G 506M 517M
How to adjust the swappiness value<\/strong>
Swappiness is a Linux kernel property that defines how often the system will use the swap space. Swappiness can have a value between 0 and 100. A low value will make the kernel to try to avoid swapping whenever possible, while a higher value will make the kernel to use the swap space more aggressively.
The default swappiness value is 60. You can check the current swappiness value by typing the following command:
cat \/proc\/sys\/vm\/swappiness
Output:60
While the swappiness value of 60 is OK for most Linux systems, for production servers, you may need to set a lower value.
For example, to set the swappiness value to 10, you would run:
sudo sysctl vm.swappiness=10
To make this parameter persistent across reboots append the following line to the \/etc\/sysctl.conf file:
\/etc\/sysctl.conf
vm.swappiness=10
The optimal swappiness value depends on your system workload and how the memory is being used. You should adjust this parameter in small increments to find an optimal value.
How to remove Swap File<\/strong>
If for any reason you want to deactivate and remove the swap file, follow these steps:
\u00a0 \u00a0 First, deactivate the swap by typing:
\u00a0 \u00a0 sudo swapoff -v \/swapfile
\u00a0 \u00a0 Remove the swap file entry \/swapfile swap swap defaults 0 0 from the \/etc\/fstab file.
\u00a0 \u00a0 Finally, delete the actual swapfile file using the rm command:
\u00a0 \u00a0 sudo rm \/swapfile<\/p>\n","protected":false},"excerpt":{"rendered":"

How to add Swap FileFollow these steps to add 1GB of swap to your server. If you want to add 2GB instead of 1 GB, replace 1G with 2G.\u00a0 \u00a0 Create a file that will be used for swap:\u00a0 \u00a0 sudo fallocate -l 1G \/swapfile\u00a0 \u00a0 If fallocate is not installed or if you get […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[15],"tags":[],"class_list":["post-87","post","type-post","status-publish","format-standard","hentry","category-file-management"],"_links":{"self":[{"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/87","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=87"}],"version-history":[{"count":1,"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/87\/revisions"}],"predecessor-version":[{"id":88,"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/87\/revisions\/88"}],"wp:attachment":[{"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=87"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=87"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/triosdevelopers.com\/J.Smith\/rjeffsmith.ca\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=87"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}