Re: Memory usage Debian Jessie (stable)

[Dan Christensen <jdc@uwo.ca>]

Jan-Rens Reitsma <jan.rens.reitsma@gmail.com> writes:

> $ free -h
>              total       used       free     shared    buffers     cached
> Mem:          3.7G       3.5G       182M       153M       363M       2.1G
> -/+ buffers/cache:       1.0G       2.7G
> Swap:         7.6G         0B       7.6G
>
> 3.5 GB used of 3.7 GB available memory,
> with 2.1 GB available for caching and 182 MB free,
> 1.0 GB of the available cache and memory is used,
> no swap space used.

That's not a correct interpretation of the output of "free".  What that
output says is that 3.5GB is used, but of that, 363MB + 2.1GB = 2.5GB is
currently being used for buffers and cache.  The memory used for buffers
and cache can be made available very quickly, so the second line shows
how much is used (1.0GB) and free (2.7GB) with the buffer and cache
usage ignored.  So the real thing to take away from the above is in
the second line:  only 1.0GB is used and 2.7GB is free.  See

  http://unix.stackexchange.com/questions/33541/free-output-format/33549#33549

Dan