Linux Swap partition creation and management

Swap partition creation and management 1. View Swap partitions

[[email protected] ~]# free -h                         total       used       free     shared    buffers     cachedMem:          2.0G       1.0G       944M       1.5M       265M       341M-/+ buffers/cache:       454M       1.5GSwap:         4.0G         0B       4.0G           #swap分区大小[[email protected] ~]# fdisk -lDisk /dev/sda: 53.7 GB, 53687091200 bytes255 heads, 63 sectors/track, 6527 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisk identifier: 0x0004c723     Device Boot      Start         End      Blocks   Id  System/dev/sda1   *           1          26      204800   83  LinuxPartition 1 does not end on cylinder boundary./dev/sda2              26         548     4194304   82  Linux swap / Solaris   #swap挂载地方Partition 2 does not end on cylinder boundary./dev/sda3             548        6528    48028672   83  Linux

2. Turn off swap

[[email protected] ~]# swapoff /dev/sda2[[email protected] ~]# free -h                         total       used       free     shared    buffers     cachedMem:          2.0G       1.1G       923M       1.5M       265M       341M-/+ buffers/cache:       475M       1.5GSwap:           0B         0B         0B[[email protected] ~]# swapon /dev/sda2 [[email protected] ~]# free -h                         total       used       free     shared    buffers     cachedMem:          2.0G       1.0G       944M       1.5M       265M       341M-/+ buffers/cache:       455M       1.5GSwap:         4.0G         0B       4.0G

3.swap Partition expansion

[[email protected] ~]# dd if=/dev/zero of=/opt/swapfile bs=1M count=1024      #创建一个swap分区1024+0 records in1024+0 records out1073741824 bytes (1.1 GB) copied, 19.2751 s, 55.7 MB/s[[email protected] ~]# mkswap /opt/swapfile                #格式化成swap格式mkswap: /opt/swapfile: warning: don‘t erase bootbits sectors                on whole disk. Use -f to force.Setting up swapspace version 1, size = 1048572 KiBno label, UUID=565ba456-ae47-4749-a7f7-1cd26f37bdbd[[email protected] ~]# swapon /opt/swapfile               #启用该swap分区，并会自动合并到原来的swap分区上[[email protected] ~]# free -h                         total       used       free     shared    buffers     cachedMem:          2.0G       1.9G       101M       1.5M       264M       1.1G-/+ buffers/cache:       466M       1.5GSwap:         5.0G         0B       5.0G

Linux Swap partition creation and management