9/1 I'm using RedHat 8 on a machine with 512 MB RAM and I only have
35 MB of RAM free according to top even with nothing running but
the OS. I added up the memory for the 10 biggest processes and
only got 58 MB. Does RH 8 really use around 400 MB of RAM???
\_ The rest of memory is probably used to cache filesystem access.
Take a look at the output of "free" to see how much is used for
cache and such.
\_ Yes, this is one of those funky things about Linux. You can't
trust standard tools to tell you how much memory is in use or
available for other programs. You can use other things to sort
of calculate backwards such as the other person says or you can
look at swap in use but that's just an alternative, not better.
You might consider writing a script that will parse your top
output, calculate, and print the numbers you're looking for. The
memory used for file cache, etc, isn't permanently lost to the
system, btw. Memory will be released from cache as you load more
programs. |