Preparing to use ziomon

When you collect traces with ziomon, you require 2 MB of Vmalloc space for each SCSI device node and CPU.

About this task

For instance, if you have a single SCSI device that is attached through multipathing as /dev/sda, /dev/sdb and /dev/sdc on a system with two CPUs, you would need 3×2×2 MB = 12 MB of Vmalloc space.

To check the amount of available Vmalloc space, issue the command:

cat /proc/meminfo | grep Vmalloc

The ziomon data collection process can be corrupted if the cpuplugd deamon is running. Disable cpuplugd during the data collection process. To check whether the cpuplugd deamon is running use:

service cpuplugd

See Device Drivers, Features, and Commands, SC33-8411 for further details on cpuplugd.