Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 24 Jul 2003 12:17:26 +1000
From:      Peter Jeremy <peter.jeremy@alcatel.com.au>
To:        Brooks Davis <brooks@one-eyed-alien.net>
Cc:        freebsd-stable@freebsd.org
Subject:   Re: malloc does not return null when out of memory
Message-ID:  <20030724021726.GJ430@gsmx07.alcatel.com.au>
In-Reply-To: <20030723224436.GD22166@Odin.AC.HMC.Edu>
References:  <20030723173427.GA72876@vmunix.com> <20030723140329.C92624@carver.gumbysoft.com> <20030723221336.GA26555@pit.databus.com> <20030723223654.GA24008@moghedien.mukappabeta.net> <20030723224436.GD22166@Odin.AC.HMC.Edu>

next in thread | previous in thread | raw e-mail | index | archive | help
On 2003-Jul-23 15:44:36 -0700, Brooks Davis <brooks@one-eyed-alien.net> wrote:
>On Thu, Jul 24, 2003 at 12:36:54AM +0200, Matthias Buelow wrote:
>> Wasn't there a sysctl flag to enable/disable overcommitting?
>> I think I remember something but I can't find it; it might
>> not have been on FreeBSD.
>
>No there isn't.  Overcommit is a fundamental design feature of the BSD
>VM.  If you don't like it, find an OS that doesn't do it.  The only one
>I can think of off the top of my head in Irix where I've found it to be
>a serious pain in the ass.

DEC/Compaq/HP Tru64 has a flag to enable/disable overcommit.  The
major benefit seems to accrue to disk vendors with all the additional
swap space needed.

FreeBSD behaviour in the face of swap shortage is a regular and
popular discussion topic.  I suggest that a perusal of the archives
will probably answer any questions.  If anyone wishes to suggest a
"solution" to FreeBSD's behaviour when there is a shortage of swap,
please include patches.

Peter



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030724021726.GJ430>