> OK, I guess I'm starting to understand how Linux manages disk caching, and the meaning of "buffered".
> In fact:
> # free -m
> total used free shared buff/cache available
> Mem: 32094 2799 1074 154 28220 28810
> Swap: 36168 168 36000
> ...so I have 28810MB RAM available.
Well, sort of. You have 1074 MB free for use if anything wants it
immediately. The rest of the 28810 MB is being used by the kernel as
temporary storage for open disk files etc and will take some cycles to
clean out before it can be used by other things. So it is available for
allocation to programs, but the alloc will be somewhat slow.
(It's been a few decades since I dealt with these things in detail, so
I'm not sure exactly on best practice with these GB-sized machines. But
that looks reasonably healthy to me: 1GB RAM free and almost no swapping.)