Usage of Vmalloc Address Space
|Distribution:||official part of Check_MK|
The linux kernel keeps a part of the available address
space free for usage by device drivers, e.g. for address
mappings of IO devices into the physical address space.
An example is the graphics driver used by the X server,
which needs address mappings for communicating with
the hardware. In /proc/meminfo that area is called
VmallocTotal. On 32 bit architectures this area has
a very limited size and is subject to fragmentation or
consumption by buggy graphics drivers.
This check monitors the current usage of the the vmalloc
address space and also the size of the largest available
chunk (indicating the degree of fragmentation).
One service is created if VmallocTotal is available in /proc/meminfo
and only if the total size of the vmalloc area is less then 4 GB.
This is generally only possible for 32 bit architectures.
Please add mem.vmalloc to ignored_checktypes if you do not need this check.