Swappiness is a property of the Linux kernel that changes the balance between swapping out runtime memory, as opposed to dropping pages from the system page cache. Swappiness can be set to values between 0 and 100 inclusive. A low value means the kernel will try to avoid swapping as much as possible where a higher value instead will make the kernel aggressively try to use swap space. The default value is
60, and for most desktop systems, setting it to 100 may affect the overall performance, whereas setting it lower (even 0) may improve interactivity (by decreasing response latency.)
||The kernel will swap only to avoid an out of memory condition.|
||The default value.|
||The kernel will swap aggressively which may affect over all performance.|
To temporarily set the swappiness in Linux, write the desired value (e.g.
/proc/sys/vm/swappiness using the following command, running as root user:
# Set the swappiness value as root echo 10 > /proc/sys/vm/swappiness # Alternatively, run this as a non-root user sudo sysctl -w vm.swappiness=10 # Verify the change cat /proc/sys/vm/swappiness 10
Permanent changes are made in
/etc/sysctl.conf via the following configuration line (inserted if not present previously):
vm.swappiness = 10
- van Riel, Rik. "Documentation for /proc/sys/vm/* in Github". Linus Torvald's kernel tree. Github. Retrieved 3 March 2013.
- Documentation for /proc/sys/vm/* kernel version 2.6.29 authoritative documentation
- "2.6 swapping behavior". May 5, 2004. Retrieved June 8, 2010.
- "Linux: Tuning Swappiness". April 29, 2004. Retrieved June 8, 2010.