Subject: Re: Swap overcommit (was Re: Replacement for grep(1) (part 2))
To: Ben Rosengart <ben@skunk.org>
From: Michael Richardson <mcr@sandelman.ottawa.on.ca>
List: tech-userlevel
Date: 07/14/1999 16:01:20
>>>>> "Ben" == Ben Rosengart <ben@skunk.org> writes:
Ben> On Wed, 14 Jul 1999, John Nemeth wrote:
>> On one system I administrate, the largest process is typically
>> rpc.nisd (the NIS+ server daemon). Killing that process would be a
>> bad thing (TM). You're talking about killing random processes. This
>> is no way to run a system. It is not possible for any arbitrary
>> decision to always hit the correct process. That is a decision that
>> must be made by a competent admin. This is the biggest argument
>> against overcommit: there is no way to gracefully recover from an out
>> of memory situation, and that makes for an unreliable system.
Ben> $DEITY on a pogo stick, how many times do we have to hear the same
Ben> hypothetical argument?
Ben> Tell me, Mr. Nemeth, has this ever happened to you? Have you ever
Ben> come *close*?
Uh, since we don't run overcommit, the answer is specifically *NO*.
We have never had lack of swap space randomly kill one of our processes.
This is good, and this is the way we want to keep it.
I have had it happen on other systems. (Solaris, AIX) It was very
mystifying to diagnose. Sure, the systems were misconfigured for what we
were trying to do, but if I wanted build a custom system for every
application.... well... I'd be running NT.
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