Difference between revisions of "Swap"
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| Line 22: | Line 22: | ||
check your swappiness values with | check your swappiness values with | ||
cat /pro/sys/vm/swappiness | cat /pro/sys/vm/swappiness | ||
| − | + | (the value 60 means here use swap when less then 60% of RAM free) | |
| + | by | ||
You can change it in a run-time (after restart default swap settings will beback) , effect is instant | You can change it in a run-time (after restart default swap settings will beback) , effect is instant | ||
echo '0' > /pro/sys/vm/swappiness | echo '0' > /pro/sys/vm/swappiness | ||
| − | You can set the value permanent adding line at end of /etc/sysctl.conf | + | You can set the value permanent by adding the line at end of /etc/sysctl.conf |
vm.swappiness=0 | vm.swappiness=0 | ||
| − | ( | + | (0 value means to use swap only when there is no Ram free) |
===Make swap empty=== | ===Make swap empty=== | ||
swapoff -a | swapoff -a | ||
swapon -a | swapon -a | ||
Revision as of 11:22, 7 May 2020
Swap
Swap usage can lead to performance degradation of your server. So we highly recommend to disable swap space and increase the memory.
How to disable
root@vmsniff:~# swapoff -a
Then edit the /etc/fstab file and comment out the swap lines. E.g.
proc /proc proc defaults 0 0 # / was on /dev/md0 during installation UUID=17e56a9a-0f42-44ca-90e8-570315708def / xfs relatime 0 1 # swap was on /dev/sda2 during installation #UUID=0a403f5e-0505-4055-a219-70217b6b74d1 none swap sw 0 0 # swap was on /dev/sdb2 during installation #UUID=4cf42564-4339-42ed-b7ec-29644a3085f1 none swap sw 0 0
How to configure
Most distributions have set by default to use swap when Ram usage exceeds 40% check your swappiness values with
cat /pro/sys/vm/swappiness
(the value 60 means here use swap when less then 60% of RAM free) by You can change it in a run-time (after restart default swap settings will beback) , effect is instant
echo '0' > /pro/sys/vm/swappiness
You can set the value permanent by adding the line at end of /etc/sysctl.conf
vm.swappiness=0
(0 value means to use swap only when there is no Ram free)
Make swap empty
swapoff -a swapon -a