Re: 2.4.17:Increase number of anonymous filesystems beyond 256?

[Pete Zaitcev <zaitcev@redhat.com>]

> From: Rainer Krienke <krienke@uni-koblenz.de>
> Date: Fri, 25 Jan 2002 08:28:13 +0100

> > Rainer, you missed the point. Nobody cares about small things
> > such as "cannot start nfsd" while your 4096 mounts patch
> > simply CORRUPTS YOUR DATA TO HELL.
> 
> Well I never said, I really knew what I was doing:-).  Thats exacly why I 
> asked about why to use more major devices? OK the anser to this question 
> seems to be that minor devices may only be 8 bit due to the static nature of 
> some kernel structures. Right?

Close enough... Actual reason is the implementation of MINOR().

> > If you need more than 1200 mounts, you have to add more majors
> > to my patch. There is a number of them between 115 and 198.
> > I suspect scalability problems may become evident
> > with this approach, but it will work.
> 
> The solution Richard posted seems to be interesting at this point isn't it?

I thought about the rgooch's suggestion, it sounds good for 2.5.
Red Hat do not ship devfs enabled currently, and I cannot use his
allocation function if someone uses static majors, or some modules
may not load. The patch does include a safety element (majorhog_xxx)
that reserves majors properly. The devfs would make that unnecessary.

-- Pete