Service graphs
	
Graph Information
This graph shows what the machine uses memory for.
	| Field | Internal name | Type | Warn | Crit | Info | 
	| apps | apps | gauge |  |  | Memory used by user-space applications. | 
	| page_tables | page_tables | gauge |  |  | Memory used to map between virtual and physical memory addresses. | 
	| swap_cache | swap_cache | gauge |  |  | A piece of memory that keeps track of pages that have been fetched from swap but not yet been modified. | 
	| slab_cache | slab | gauge |  |  | Memory used by the kernel (major users  are caches like inode, dentry, etc). | 
	| shmem | shmem | gauge |  |  | Shared Memory (SYSV SHM segments, tmpfs). | 
	| cache | cached | gauge |  |  | Parked file data (file content) cache. | 
	| buffers | buffers | gauge |  |  | Block device (e.g. harddisk) cache. Also where "dirty" blocks are stored until written. | 
	| unused | free | gauge |  |  | Wasted memory. Memory that is not used for anything at all. | 
	| swap | swap | gauge |  |  | Swap space used. | 
	| vmalloc_used | vmalloc_used | gauge |  |  | 'VMalloc' (kernel) memory used | 
	| committed | committed | gauge |  |  | The amount of memory allocated to programs. Overcommitting is normal, but may indicate memory leaks. | 
	| mapped | mapped | gauge |  |  | All mmap()ed pages. | 
	| active | active | gauge |  |  | Memory recently used. Not reclaimed unless absolutely necessary. | 
	| inactive | inactive | gauge |  |  | Memory not currently used. |