Hello all,
I am facing a memory related issue on my linux that is CentOS 4.0. What I see as an output of top command, free command is that memory usage is almost 90% which is quite high without much load on the system. This is continuously showing 90% or so of memory usage with top or free command.
However, when look at the later part of the output of the top command that is for processes (and sort it by %MEM usage by typing interactive M) and I sum up for individual processes, it is hardly exceeding 15%. The sum of %MEM is about 13% for the top 5 or 6 processes and beyond the 6th process, %MEM displayed is 0 (0%).
How do we explain this anomaly ? If the memory usage reported by top and free is fine, how do I find where the memory is being used? Also, what is the perfect way to find how much actual physical memory is being used by the system ?