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When typing ps aux, what does each column of the output mean? For example
$ ps aux
timothy 29217 0.0 0.0 11916 4560 pts/21 S+ 08:15 0:00 pine
root 29505 0.0 0.0 38196 2728 ? Ss Mar07 0:00 sshd: can [priv]
can 29529 0.0 0.0 38332 1904 ? S Mar07 0:00 sshd: can@notty
Thanks and regards!
Can you say a little more about the differences between VSZ and RSS? Thanks. – Qian Chen – 2015-06-11T15:53:53.723
3RSS is the amount of physical memory this process is using. Note that this includes any memory that's shared with other processes (eg if other processes are loaded from same executable or libraries) so it may over-report memory usage. VSZ is the size of the virtual memory space - do not be mislead by this as it's not all "used" memory. It includes memory in use (RSS), memory that's swapped, but usually the majority is just additional addressing space that hasn't actually had any real memory allocated to it - in order to use that space, more memory would need to be given to the process. – thomasrutter – 2015-07-21T01:42:01.067
2I tried to think of an analogy. Let's say you're eating dinner so you're sharing a limited supply of food with other people. RSS is the amount of food currently on your plate. VSZ is the size of your plate. Not all of your plate is food and it's not relevant to how much food you've claimed. – thomasrutter – 2015-07-21T01:47:16.623
26You could add e.g. that VSZ and RSS are output in KiB, not bytes as I first thought... – Christian Davén – 2012-10-22T08:57:07.717