Overview
Parameters
The following parameters are available for this item:
active - memory currently in use or very recently used, and so it is in RAM
anon - memory not associated with a file (cannot be re-read from it)
available - available memory, calculated differently depending on the platform (see the table below)
cached - cache for various things
file - cache for contents of recently accessed files
free - memory that is readily available to any entity requesting memory
inactive - memory that is marked as not used
pavailable - ‘available’ memory as percentage of ‘total’ (calculated as /*100)
pused - ‘used’ memory as percentage of ‘total’ (calculated as /*100)
slab - total amount of memory used by the kernel to cache data structures for its own use
total - total physical memory available
used - used memory, calculated differently depending on the platform (see the table below)
wired - memory that is marked to always stay in RAM. It is never moved to disk.
Some of these parameters are platform-specific and might not be available on your platform. See Items supported by platform for details.
Platform-specific calculation of available and used:
So inactive memory is both used and available simultaneously. Because of this, the vm.memory.size[used] item is designed for informational purposes only, while vm.memory.size[available] is designed to be used in triggers.