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From: Terry Lambert <terry@lambert.org>
Message-Id: <199608270220.TAA23773@phaeton.artisoft.com>
Subject: Re: vclean (was The VIVA file system)
To: michaelh@cet.co.jp
Date: Mon, 26 Aug 1996 19:20:17 -0700 (MST)
Cc: terry@lambert.org, eric@ms.uky.edu, freebsd-fs@FreeBSD.ORG,
        current@FreeBSD.ORG
In-Reply-To: <Pine.SV4.3.93.960827092559.16443D-100000@parkplace.cet.co.jp> from "Michael Hancock" at Aug 27, 96 09:41:37 am
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> > The address space compression is interesting for vnode-based buffering;
> > FreeBSD currently uses this method, but... well, I've railed often
> > enough against vclean that I think everyone knows how I feel.
> 
> Some subsystems now depend on the ability to disassociate buffers from
> vnodes.  For example, kill the session leader and the session terminal is
> revoked from all children and the deadfs is associated with the vnode.
> The only call that doesn't return an error is close() and the children
> eventually exit.
> 
> I think what needs to be looked at is having more synchronized buffer
> cache/vnode recycling policies.

Inode data, disklabel data, and any other FS object which is not file
contents is not cached under the current policy.

Further, dissociating buffers from vnodes does not require that they
be returned to a global pool for clean-behind.

I think the non-opacity of vnodes is a mistake.


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.