I have read What do the "buff/cache" and "avail mem" fields in top mean? and https://askubuntu.com/questions/770108/what-do-the-changes-in-free-output-from-14-04-to-16-04-mean. But still have questions.
$ free -h
total used free shared buff/cache available
Mem: 7.7G 5.3G 268M 620M 2.1G 1.5G
Swap: 14G 874M 14G
Does "used" already include "shared"?
Can "available" be determined from other columns?
Why does "available" not equal to sum of "free" and "buff/cache"?
I thought that "buff/cache" is actually available to be used by starting a new process, so why is "available" smaller than "buff/cache"?
What columns does "total - used" (2.4G) consist of? Why isn't it the same as "available"?
Thanks.
top
output mean the same as infree
output? – Tim Oct 29 '18 at 14:19kmalloc
allocations, page caches, etc. Again, we’re discussing physical memory, so where they happen in the address space isn’t particularly relevant (but the kernel maps them in its own address space). – Stephen Kitt Oct 29 '18 at 15:58