physical memory free
This lists the free (available) real memory space on the specified hosts, in kilobytes.
Physical memory is for working processes. Linux puts idle processes onto the SWAP memory. This means you can have a virtual memory that is almost full, and still have available space in the physical memory.
Both Physical memory free and Physical memory % free are divided into three sections:
- Physical memory (hardware or hard-drive partition)
- Buffer
- Cache
This is used when processes load documents. You can free this when the system is low on memory. You can also have a virtual memory that is almost fully used. The available space is increased by flushing the cache.