To display the current value of a tunable that is being used by VxVM or DMP, use the following commands with the
/proc file system:
cat < /proc/sys/vxvm/vxio/vol_maxio
cat < /proc/sys/vxdmp/dmp_enable_restore_daemon
To change the value of a VxVM or DMP tunable, specify the new value using the
You must then shut down and reboot the system for the change to take effect. The new value persists across system reboots until it is next changed.
For example, the following command sets the value of
vol_maxio to 8192:
vxvoltune vol_maxio 8192
vxdmptuneutilities modify the tunable values stored in the
/etc/vx/vxdmp_tunablesfiles respectively. It is recommended that you use the
vxdmptunecommands to change the values stored in these files. Do not edit these files directly.
You can use the
vxdmptune commands to display the current values of a tunable parameter that is set in the
DMP tunables can also be set by using the
vxdmpadm command as shown here:
vxdmpadm settune dmp_tunable=value
A value that is set in this way overrides that defined in the
The values of these tunables can be displayed by using this command:
vxdmpadm gettune [dmp_tunable]
vxdmpadm command also allows you to configure how DMP responds to I/O errors at the level of the paths to individual arrays.
See "Administering DMP using vxdmpadm" on page 150.