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From: Lyndon Nerenberg <lyndon@orthanc.ca>
Date: Sat, 27 May 2006 23:12:29 -0700
To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Cc: arch@freebsd.org
Subject: Re: A sort of plan for consoles in FreeBSD
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Just as a neutral data point ...

CTIX (Convergent Technologies SVRx from the mid 1980s) ran /dev/ 
console such that writes went into an in-kernel circular buffer.   
Reads from /dev/console would drain the contents of that buffer.

I didn't like the read behaviour; it would have been more useful if  
reads didn't empty the buffer.  But I did like how easy it was to  
examine the buffer with crash after a panic.  While this isn't  
directly applicable to BSD, I do like the concept of having that  
kernel message log.  It addresses the issues that others have raised  
about syslog not having time to commit to disk, or do a network write  
during kernel death.  I would gladly pay for a meg or so of kernel  
memory to hold such a write buffer (size tunable by sysctl).

--lyndon