Struct RAM 

pub struct RAM {

    pub total: Size,
    pub free: Size,
    pub available: Size,
    pub buffers: Size,
    pub cached: Size,
    pub swap_cached: Size,
    pub active: Size,
    pub inactive: Size,
    pub active_anon: Size,
    pub inactive_anon: Size,
    pub active_file: Size,
    pub inactive_file: Size,
    pub unevictable: Size,
    pub mlocked: Size,
    pub swap_total: Size,
    pub swap_free: Size,
    pub zswap: Size,
    pub zswapped: Size,
    pub dirty: Size,
    pub writeback: Size,
    pub anon_pages: Size,
    pub mapped: Size,
    pub shmem: Size,
    pub kreclaimable: Size,
    pub slab: Size,
    pub sreclaimable: Size,
    pub sunreclaim: Size,
    pub kernel_stack: Size,
    pub page_tables: Size,
    pub sec_page_tables: Size,
    pub nfs_unstable: Size,
    pub bounce: Size,
    pub writeback_tmp: Size,
    pub commit_limit: Size,
    pub commited_as: Size,
    pub vmalloc_total: Size,
    pub vmalloc_used: Size,
    pub vmalloc_chunk: Size,
    pub percpu: Size,
    pub hardware_corrupted: Size,
    pub anon_huge_pages: Size,
    pub shmem_huge_pages: Size,
    pub shmem_pmd_mapped: Size,
    pub cma_total: Option<Size>,
    pub cma_free: Option<Size>,
    pub file_huge_pages: Size,
    pub file_pmd_mapped: Size,
    pub unaccepted: Size,
    pub huge_pages_total: u32,
    pub huge_pages_free: u32,
    pub huge_pages_rsvd: u32,
    pub huge_pages_surp: u32,
    pub huge_page_size: Size,
    pub huge_tlb: Size,
    pub direct_map_4k: Size,
    pub direct_map_2m: Size,
    pub direct_map_1g: Size,
}

A structure containing data from the /proc/meminfo file

Fields

total: Size

Total usable physical RAM (excludes reserved/firmware memory)

free: Size

Completely unused physical RAM. Often misleadingly low due to caching

available: Size

Best estimate of memory available for new apps (accounts for caches/reclaimable memory)

buffers: Size

Temporary storage for raw disk blocks (e.g. filesystem metadata)

cached: Size

Page cache for files read from disk (reclaimed when apps need memory)

swap_cached: Size

Memory swapped out but later accessed, now present in both RAM and swap

active: Size

Recently used memory (harder to reclaim)

inactive: Size

Less recently used memory (eased to reclaim)

active_anon: Size

Active anonymous pages (e.g. heap/stack, not file-backed)

inactive_anon: Size

Inactive anonymous pages

active_file: Size

Active file-backed pages (cached files)

inactive_file: Size

Inactive file-backed pages

unevictable: Size

Memory that cannot be pages out (e.g. locked with mlock())

mlocked: Size

Memory that is locked (cannot be swapped out)

swap_total: Size

Total amount of swap space available

swap_free: Size

Amount of swap space that is currently unused

zswap: Size

zswapped: Size

dirty: Size

Data waiting to be written to disk

writeback: Size

Data actively being written to disk

anon_pages: Size

Non file-backed pages mapped into user-space page tables

mapped: Size

Files (like libraries) that have been mapped into memory (also includes tmpfs/shmem)

shmem: Size

Total memory used by shared memory (shmem) and tmpfs

kreclaimable: Size

Kernel allocations that the kernel will attempt to reclaim under memory pressure (includes SReclaimable and other reclaimable slabs)

slab: Size

In-kernel data structures cache (includes SReclaimable and SUnreclaim)

sreclaimable: Size

Part of Slab that might be reclaimed, such as caches for directory inodes, etc.

sunreclaim: Size

Part of Slab that cannot be reclaimed

kernel_stack: Size

Memory used by kernel stacks

page_tables: Size

Memory used by page tables (to map virtual to physical addresses)

sec_page_tables: Size

nfs_unstable: Size

Memory that has been sent to the NFS server but not yet committed to stable storage

bounce: Size

Memory used for block device bounce buffers (rarely used on modern systems)

writeback_tmp: Size

Memory used by FUSE for temporary writeback buffers

commit_limit: Size

Based on the overcommit ratio, this is the total amount of memory currently available to be allocated

commited_as: Size

he amount of memory currently allocated by the system. The kernel may overcommit this

vmalloc_total: Size

Total size of vmalloc memory area

vmalloc_used: Size

Amount of vmalloc area which is used

vmalloc_chunk: Size

Largest contiguous block of free vmalloc space

percpu: Size

Memory used for per-cpu allocations (each CPU has its own block)

hardware_corrupted: Size

Memory that the kernel identified as corrupted (when CONFIG_MEMORY_FAILURE is enabled)

anon_huge_pages: Size

Non-file backed huge pages mapped into user-space page tables (transparent hugepages)

shmem_huge_pages: Size

Huge pages used by shared memory (shmem) and tmpfs.

shmem_pmd_mapped: Size

shmem/tmpfs memory that is mapped into user space with huge pages

cma_total: Option<Size>

Total CMA (Contiguous Memory Allocator) area

cma_free: Option<Size>

Free memory in the CMA area

file_huge_pages: Size

file_pmd_mapped: Size

unaccepted: Size

huge_pages_total: u32

huge_pages_free: u32

huge_pages_rsvd: u32

huge_pages_surp: u32

huge_page_size: Size

huge_tlb: Size

direct_map_4k: Size

direct_map_2m: Size

direct_map_1g: Size

Implementations

impl RAM

pub fn new() -> Result<Self>

pub fn used_ram(&self, base: u8) -> Size

pub fn usage_percentage(&self) -> Option<f64>

Trait Implementations

impl Clone for RAM

fn clone(&self) -> RAM

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RAM

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for RAM

fn default() -> RAM

Returns the “default value” for a type.

impl Serialize for RAM

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl ToJson for RAM

fn to_json(&self) -> Result<String>

where Self: Serialize,

Convert object data to machine-readable JSON format (without unnecessary indentation and newline transitions)

fn to_json_pretty(&self) -> Result<String>

where Self: Serialize,

Convert object data to human-readable JSON format (“pretty”; with additional newline transitions and indentation)