For any OS, effective memory management is very important. In OS, physical memory and virtual memory is required to run any process. When system is running out of memory, kernel will move inactive process data into virtual memory to free physical memory. Kernel divides physical memory into chunks called pages. The process of moving active process pages to virtual memory is called swapping. Swap space can be disk partition or file.
Partition id of swap partition is 82
#mkkswap /dev/hda2 Mark as swap partition
#swapon /dev/hda2 Activate the swap partition
#swapoff /dev/hda2 Deactivate the swap partition
#fallocate -l 512m /mnt/512MiB.swap Create file
#dd if=/dev/zero of=/swapfile bs=1024 count=1048576 Create file
#mkswap /swapfile; swapon /swapfile; swapoff /swapfile Mark as swap file
In linux 2.6 kernel you can tune swapiness kernel parameter. Swapiness value can be 0 to 100; higher values leads to more swap will occur. Default swapiness is 60.
#echo 65 > /proc/sys/vm/swapiness Set swapiness value
priority is a value between -1 and 32767. Higher num‐bers indicate higher priority
#swapon –p 22 /mnt/512MiB.swap Set the swap prioroty
#sysctl -w vm.swappiness=30