System Management Concepts: Operating System and Devices

Managing Paging Spaces

The following commands are used to manage paging space:

The mkps command uses the mklv command with a specific set of options when creating a paging space logical volume. To create NFS paging spaces, the mkps command uses the mkdev command with another set of options. Some of the following options are required for all logical volume paging spaces:

• Paging type
• No bad-block relocation
• No mirroring.

The following options are used to maximize paging performance with a logical volume:

• Allocate in the middle of the disk to reduce disk arm travel
• Use multiple paging spaces, each allocated from a separate physical volume.

For NFS paging spaces, the mkps command needs the host name of the NFS server and the path name of the file that is exported from the server.

The swapon command is used during early system initialization to activate the initial paging-space device. During a later phase of initialization, when other devices become available, the swapon command is used to activate additional paging spaces so that paging activity occurs across several devices.

The swapoff command is used to deactive a paging space without rebooting the system. Information in the paging space is moved to other other active paging space areas. The deactivated paging space can then be removed using the rmps command.

The /etc/swapspaces file specifies the paging-space devices that are activated by the swapon -a command. A paging space is added to this file when it is created by the mkps -a command, removed from the file when it is deleted by the rmps command, and added or removed by the chps -a command.