I have a small VPS server that I use as both a micro and development webhost and as a platform for whenever I want to do something somewhere that isn't my laptop. It's somewhat underspec with only 128M ram available (256 burst), but it works.
To deal with this, I have turned down a bunch of settings, etc. However, it still ends up reaching my cap whenever I try to do stuff.
I have done a bunch of research into this, but can't find anything other than people who mistook buffers and cache for actual process memory use.
I keep feeling like something doesn't add up right, so I finally tried
sh-3.2$ free
total used free shared buffers cached
Mem: 131072 131072 0 0 0 0
-/+ buffers/cache: 131072 0
Swap: 0 0 0
sh-3.2$ ps aux | awk '{sum += $4} END {print sum}'
67.4
sh-3.2$
So while all of my processes add up to 2/3 of my total, I'm somehow still entirely out of ram. htop agrees with both of them (bar at the top says 128M/128M; numbers agree).
Is it possible that free isn't keeping track correctly or something due to the VPS? Or is there actually something mysterious using 30% of my available ram?