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 id 1XizjG-0043nU-RE; Mon, 27 Oct 2014 23:54:03 -0600
Date: Tue, 28 Oct 2014 13:52:49 +0800
From: Erich Dollansky <erichsfreebsdlist@alogt.com>
To: Jim Pazarena <fquest@paz.bz>
Subject: Re: out of swap space
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Hi,

On Mon, 27 Oct 2014 12:57:55 -0700
Jim Pazarena <fquest@paz.bz> wrote:

> There is a lot of historical chatter about the amount of swap space 
> required.
> But for my question, I haven't seen discussion:
> What HAPPENS when the system flags "out of swap space".
> Does a process die? or does the system merely become very sluggish?
> I have dozens of "out of swap space" messages, but I cannot find any 
> dead and/or failed jobs.

I expect that nothing much will happen when the program is well behaved
except some error messages from the program requesting the memory which
is not available. When the program is not able to handle failed malloc
requests, you should get a dump. The dump will then be for the wrong
reason. It could be that the program with the failed request writes
nothing to the log files but only to the screen.

It is a different story when the kernel itself is affected. The result
can be anything from a simple error message in the logs to a kernel
dump.

Erich