*BSD News Article 69770


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From: Andrew Gordon <andrew.gordon@net-tel.co.uk>
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: Re: MFS - Why?
Date: Thu, 30 May 1996 11:55:38 GMT
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nsayer@quack.kfu.com (Nick Sayer) wrote:
>A lot of the time swap space is unused. Why? Because you have to plan
>for a maximum case, not an average case. Disk space you set aside for
>swap is therefore essentially wasted unless you spend a lot of time
>near maximal VM allocation. This is the one thing other OSes that have
>VM (win95, macos) have over Unix: they use unused disk space as swap
>transparently while Unix must have explicitly allocated swap 

You can use the vnode driver (see vnconfig(8)) to allow swapping into a
regular file.  It may not be quite as convenient as some other OSs,
but it certainly solves the problem.