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Date: Wed, 01 Oct 2003 06:39:47 +0000
From: Jens Rehsack <rehsack@liwing.de>
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To: Kevin Oberman <oberman@es.net>
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cc: freebsd-current@freebsd.org
Subject: Re: Improvements to fsck performance in -current ...?
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Kevin Oberman wrote:

[...]

> Current has two major changes re speeding up fsck.
> 
> The most significant is the background operation of fsck on file
> system with soft updates enabled. Because of the way softupdates
> works, you are assured of metadata consistency on reboot, so the file
> systems can be mounted and used immediately with fsck started up in
> the background about a minute after the system comes up.

Be careful what you promise :-)
Most new disks have an own disk cache and some of them have a
write cache enabled. In case of a hardware failure (or power
failure) this data may get lost and the disk's metadata isn't
consistent. It's only when no write cache below the system
is active.

Jens