Linux READFILE System Call Revived Now That It Might Have A User

[tajjada]

Reading your response i'm like.. WTF.?.... Youi probably just totally misunderstood me.
I know that the monitoring software isn't visible when it's not open..
I'm not sure what you try to describe there.

When you open your monitor application, it itself is - at that point while it's open - a substantial resource user. It still is very low but you'll definitely notice it popping up.
Now with readfile that statistics gathering just plain and simply takes less cycles.

Egh ... no. What? I understood you.

I agree it would take even less cycles with readfile. All I am saying is that it is not taking many cycles to begin with, and certainly does not have a significant effect on the performance of your system.

My point was that no matter how fast it is (even if it only took a microsecond to refresh), it would always be the top cpu user according to its own statistics. Do not misinterpret this to think that it is in any way resource intensive.

And no you don't "notice it". Try it. Leave a `top` process running for like a day or more. It will have refreshed many many times. Then check its total accumulated cpu time, to see how much resources it actually used in total. I bet it is going to be all the way down there near the bottom of the list.