Subject: Re: kernel vs boot-program
To: Chris G. Demetriou <cgd@postgres.Berkeley.EDU>
From: John Brezak <>
List: tech-kern
Date: 03/14/1994 17:48:24
> > I'd like to see any prior knowledge of swap removed and done via swapon. I've
> > never quite understood the need for config having to compile all potential
> > swap devices in.
> This is necessary because of the way swap device interleaving is done.
I don't think this is the only way to get this behavior. We did something
different in OSF/1. Look at the paper "OSF/1 Virtual Memory Improvements", David
Black, Usenix Mach Symposium 1991 (?). I can put the PostScript on
sun-lamp if anyone doesn't have the proceedings.

> in my posession is an extension to the swapping code, which does
> non-interleaved swapping for certain devices, e.g. 'vnode' devices,
> but they still need to be specified at config time.
Why can't you start interleaving as devices (files) get added ?

> what's the current method of doing NFS swap?
I believe (others jump in please) that it uses the NFS code to swap to a file
in NFS. It needs to have an NFS filehandle and this is one of the parts under
discussion. I really don't like having to have this mechanism. I really would
like to have an entry in /etc/fstab like

mother:/export/son/.paging_space	none	swap 	sw 0 0

And let a "swapon -a" do the work. Until this time just don't page.

> cgd

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