swap

# fdisk /dev/sda WARNING: DOS-compatible mode is deprecated. It's strongly recommended to         switch off the mode (command 'c') and change display units to         sectors (command 'u'). Command (m for help): p Disk /dev/sda: 21.5 GB, 21474836480 bytes255 heads, 63 sectors/track, 2610 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk identifier: 0x0007187a    Device Boot      Start         End      Blocks   Id  System/dev/sda1   *           1          26      204800   83  LinuxPartition 1 does not end on cylinder boundary./dev/sda2              26        1301    10240000   83  Linux/dev/sda3            1301        1562     2097152   82  Linux swap / Solaris/dev/sda4            1562        1693     1056046+  83  Linux Command (m for help): tPartition number (1-4): 4Hex code (type L to list codes): 82Changed system type of partition 4 to 82 (Linux swap / Solaris) Command (m for help): p Disk /dev/sda: 21.5 GB, 21474836480 bytes255 heads, 63 sectors/track, 2610 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk identifier: 0x0007187a    Device Boot      Start         End      Blocks   Id  System/dev/sda1   *           1          26      204800   83  LinuxPartition 1 does not end on cylinder boundary./dev/sda2              26        1301    10240000   83  Linux/dev/sda3            1301        1562     2097152   82  Linux swap / Solaris/dev/sda4            1562        1693     1056046+  82  Linux swap / Solaris Command (m for help): wThe partition table has been altered!

# partx -a  /dev/sdaBLKPG: Device or resource busyerror adding partition 1BLKPG: Device or resource busyerror adding partition 2BLKPG: Device or resource busyerror adding partition 3BLKPG: Device or resource busyerror adding partition 4# mkswap /dev/sda4Setting up swapspace version 1, size = 1056040 KiBno label, UUID=99e1751e-a38c-4f56-b80f-d80e7148608b# swapon /dev/sda4 # free -m             total       used       free     shared    buffers     cachedMem:           981        180        800          0         19         50-/+ buffers/cache:        110        870 Swap:         3079          0       3079