Subject: Re: Swap overcommit (was Re: Replacement for grep(1) (part 2))
To: Daniel C. Sobral <dcs@newsguy.com>
From: Brian F. Feldman <green@FreeBSD.org>
List: tech-userlevel
Date: 07/14/1999 12:00:55
On Thu, 15 Jul 1999, Daniel C. Sobral wrote:

> "Charles M. Hannum" wrote:
> > 
> > That's also objectively false.  Most such environments I've had
> > experience with are, in fact, multi-user systems.  As you've pointed
> > out yourself, there is no combination of resource limits and whatnot
> > that are guaranteed to prevent `crashing' a multi-user system due to
> > overcommit.  My simulation should not be axed because of a bug in
> > someone else's program.  (This is also not hypothetical.  There was a
> > bug in one version of bash that caused it to consume all the memory it
> > could and then fall over.)
> 
> In which case the program that consumed all memory will be killed.
> The program killed is +NOT+ the one demanding memory, it's the one
> with most of it.

So why don't we do something else: when we're down to a certain amount of
backing store, start collecting statistics. When we're out, we check the
statistics and find what process has been allocating most of it. We kill
that process.

> 
> --
> Daniel C. Sobral			(8-DCS)
> dcs@newsguy.com
> dcs@freebsd.org
> 
> 	"Would you like to go out with me?"
> 	"I'd love to."
> 	"Oh, well, n... err... would you?... ahh... huh... what do I do
> next?"
> 

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