total used free shared buffers cached Mem: 255040 250796 4244 0 2544 87928 -/+ buffers/cache: 160324 94716 Swap: 262136 4800 257336
Mem:
total: 物理内存总数(=used+free)
used: 已经使用的内存总数(包括buffers和cached)
shared: 被几个进程共享的内存,现在已经deprecated,总是0(当然在一些系统上也可能不是0,主要取决于free命令是怎么实现的)。
buffers: A buffer is something that has yet to be "written" to disk.
cached: A cache is something that has been "read" from the disk and stored for later use.
-/+ buffers/cache:
used: 已经使用物理内存数减去buffers和cached之后的内存使用数(160324=250796-2544-87928)
free: 空闲内存数加buffers和cached(94716=4244+2544+87928)
Swap:
不解释