A sort of plan for consoles in FreeBSD

[Lyndon Nerenberg]

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