Subject: Re: ffs fragmentation
To: Mike Cheponis <mac@Wireless.Com>
From: Manuel Bouyer <>
List: tech-kern
Date: 05/17/1999 21:19:35
On May 17, Mike Cheponis wrote
> >Ok. So imagine we support Dynaswap, and you have 10G free on our HD.
> >A user starts such a program, and you want to install emacs. How
> >surprising, there's not enough free space.
> First, this -can- be handled, as I've said, by merely setting a limit on
> what percentage (or absolute size, etc) of the disk will be allowed for
> DynaSwap.

Allowed *and* reserved. We need both.
I fear this may be much less efficient than a raw swap partition, the vm system
has much more work to do. 

The filesystem code also will need some changes to support this. If this
goes in, I gues you'll need to add it not only to ffs, but also to ext2fs
and lfs (at last).
Really, if such a thing goes in I'd prefer to see it as a dynamically
adjusted file. This would abstract the filesystem.

Manuel Bouyer, LIP6, Universite Paris VI.