"Today's post is similar in spirit, but not a replay of that previous memory/swap reporting issue. Today, we're going to take a look at two other commands that, seemingly, measure and display the same information, although with (sometimes) huge discrepancies in output. Those two commands are du and df.
"The question you'll most often see (or, perhaps, have :) is something to the effect of "Why do my outputs from du and df differ? One says I'm using more disk space than the other. Which of them is correct?" Generally you'll find that df shows more disk spaced used than du does, but the case can sometimes be the opposite. It's very rare (unless you don't use your computer, and it doesn't use itself, at all ;) that the output from the two commands match. It's actually rare that they ever come close to matching. Generally, the longer a machine is up, the greater the rift between figures becomes."
