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Date: Fri, 8 Jan 2010 18:03:39 +0100
From: Ulrich =?utf-8?B?U3DDtnJsZWlu?= <uqs@spoerlein.net>
To: Julian Elischer <julian@elischer.org>
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	Pieter de Goeje <pieter@degoeje.nl>, freebsd-hackers@freebsd.org,
	shrivatsan <shrivatsan@gmail.com>
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Cc: Pieter de Goeje <pieter@degoeje.nl>, shrivatsan <shrivatsan@gmail.com>,
	freebsd-hackers@freebsd.org
Subject: Re: Question regarding memory disks
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On Wed, 06.01.2010 at 16:27:09 -0800, Julian Elischer wrote:
> Pieter de Goeje wrote:
> > Because when you "erase" something, all it does is unlink (delete the 
> > reference to) the data. So there is currently no way the memory disk can free 
> > the memory associated with the data. That is also why you should normally use 
> > swap backed memory disks instead, or use tmpfs. These can return memory to 
> > the system.
> > 
> > The ability of the filesystem to mark certain blocks as "erased" is important 
> > not only for memory disks but also for solid state drives. It is a feature 
> > UFS2 is currently lacking unfortunately.
> 
> but is being worked on

Will this automagically work for md(4) backed UFS2 file-systems? Is this
also being worked on?

Regards,
Uli