Subject: Re: 32 bit dev_t, Revision 2
To: None <tech-kern@NetBSD.ORG>
From: Paul A Vixie <>
List: tech-kern
Date: 01/11/1998 15:33:56
> I think the %10 and %11 thing must go. There is no point to the
> frequency coded notation. This is NOT an IP address. There is no point
> to dividing it that way. Any arbitrary split will be fine, and
> allocating the first 2k to dynamic devices when no real machine has
> more than 20 or 30 devices at most is not reasonable.

can i play, too?

"640K will be enough.  after all, 128K is all the motherboard can handle."

"i can see no reason why anyone would want to have a computer in their home."

i have no feeling one way or the other about the encoding other than that
it's easier in a macro to do a bit test than a <= and a >=.  but since i
can think of several "tun"-like virtual devices i'd like to add using LKM's,
i *do* see a reason why we should allow thousands of devices per kernel.

imagine the shocked surprise of the first big iron unix sysadmin to discover
that he could only have 256 PTY's, for example.  one man's magic is another
man's technology.  argue about the encoding all you want, but please don't
consider any "reasonable" (perry's word) limits to the quantities.

the rule is, find a reasonable limit and then fudge by shifting left ~10 bits.
we will eventually be screwed anyway, but this fudging makes it happen less