/proc/meminfo on Linux displays current system-wide memory performance statistics. It provides the most complete view of system memory usage. Here is a detailed explanation of all the metrics. We can use these memory metrics to troubleshoot Linux memory issues.
MemTotal The total amount of system physical memory.
MemFree The total amount of free physical memory.
Buffers The amount of memory used for pending disk writes.
Cached The amount of memory used to cache disk reads.
SwapCached The amount of memory that exists in both the swap and the physical memory.
Active The amount of memory currently active in the system.
Inactive The amount of memory currently inactive and a candidate for swap.
HighTotal The amount of high memory (in KB).
HighFree The amount of free high memory (in KB).
LowTotal The amount of low memory (in KB).
LowFree The amount of free low memory (in KB).
SwapTotal The amount of swap memory (in KB).
SwapFree The amount of free swap memory (in KB).
Dirty Memory waiting to be written to disk.
Writeback Memory currently being written to disk.
Mapped The total amount of memory brought into a process’s virtual address space using mmap.
Slab The total amount of kernel slab memory (in KB).
Committed_AS The amount of memory required to almost never run out of memory with the current workload. Normally, the kernel hands out more memory than it actually has with the hope that applications overallocate. If all the applications were to use what they allocate, this is the amount of physical memory you would need.
PageTables The amount of memory reserved for kernel page tables.
VmallocTotal The amount of kernel memory usable for vmalloc.
VmallocUsed The amount of kernel memory used for vmalloc.
VmallocChunk The largest contiguous chunk of vmalloc’able memory.
HugePages_Total The total size of all HugePages.
HugePages_Free The total amount of free HugePages.