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From: arisawa <arisawa@ar.aichi-u.ac.jp>
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Date: Tue, 27 Jan 2015 16:03:16 +0900
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To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] protection against resource exhaustion
Topicbox-Message-UUID: 3baee4f4-ead9-11e9-9d60-3106f5b1d025

Hello,

> i think it will go the same way with fork protection.  how do you tell =
which program
> is at fault?  how do you tell a program forking at high frequency, =
with short lived
> children from a fork bomb?  (such as a busy web server.)

only system administrator knows which processes should keep running.
therefore, as Lyndon mentioned, we need a mark =E2=80=9Cdon=E2=80=99t =
kill by resource exhaustion=E2=80=9D to processes.
if automatic determination is desired, the last stage of /rc/bin/cpurc =
and /rc/bin/termrc may be the right place.

> i'm not sure i understand what you mean by "traditional programming =
style" here
> as plan 9 exists in part to break unix rules.

as Eric mentioned, we have many many codes such as
	p =3D malloc(n);
	if(p =3D=3D nil){
		...
	}
or
	switch(pid =3D fork()) {/* assign =3D */
	case -1:
		sysfatal("fork: %r");
	case 0:
		...
	default:
		...
	}
I have beeb writing codes believing those error return is working.