Messages in this thread |  | | From | (Alan Cox) | Subject | Re: dev | Date | Sat, 2 Nov 1996 10:21:00 +0000 (GMT) |
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> I'm insterested in the idea of this so-called 'devfs', which I believe > to be already implemented in FreeBSD (any comments on that implementation).
Only one: Why the hell is it in the kernel ?
> 1. Number of entries. I've just looked at my system and I have well over > 650 entries and I have nothing special on system.
All taking no data blocks. Relax. You can also prune them down if it worries you
> 2. Many unused entries. A standard setup will create many entries, even > though you don't need them. Having unused entries affects the lookup of > /dev.
Microscopically (if you dont believe me apply the cache profiling patch)
> 3. When accessed, the atime on the /dev file will be updated. This means > that when null, zero etc. is used, an update of the atime is required, > this may not cause a significant impact, however, the atime on the /dev > file does not provide any useful information. There is currently a
Its used by things like lastlogin, by some security monitors etc
> - Kernel bloating. > > This is the only reason I've seen against the idea of the devfs, and this is > certainly an issue to be concerned with. Although I've used the term devfs, > It doesn't mean a completely different FS to procfs but more likely a integral > part of it.
If you ignore the IMHO bogus atime argument in your list you can do the rest in userspace and build /dev from a master /devices or similar. We don't need a kernel module for it.
Alan
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