Re: Why would top show the processes are using swap when there is no swap space?

"jinzishuai@xxxxxxxxx" <jinzishuai@xxxxxxxxx> wrote:
Thank you both.
I am 100% sure that there is no swap space used. The /proc/swaps file
is empty and free shows 0 for swap also.

I think Floyd's idea about the code may be the case.
There are times that when I recompiled the running code, the running
code crashed.
This shouldn't happen if the whole code is loaded into the RAM at the
beginning.
But if it is as described "swapped out", then deleting the binary file
on disk would make the swap in impossible and thus I got a crash.
Thank you very much.

As Bill Marcum points out, the file will not actually be removed
and the disk space freed until all references to it are closed.

However, recompiling it and replacing it with a different binary
can indeed have the effect you are describing. I'm not sure
exactly how it works, because the compiler will (or used) refuse
to overwrite the old binary, stating that it was "busy".
However, when the binary is overwritten using cp, install, or
some other mechanisms it appears that it can happen.

--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd@xxxxxxxxxx
.

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