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RE: [2.4.0] migration to devfs



Devfs has a compatibility mode which can be turned on.  it enables the old
device paths, like /dev/hda4, to coexist with the new paths, though mount
will report the new path.

Jason

>
>
> On Sat, Jan 06, 2001 at 01:34:07PM -0500, S.Salman Ahmed wrote:
> >
> > I have one question regarding devfs: does it offer any performance
> > improvements over the traditional non-devfs setup, or is
> devfs simply a
> > 'structural' change ?
>
> i fail to see how typing:
>
> /dev/ide/host0/bus0/target0/lun0/part1
>
> instead of /dev/hda1 or /dev/wd0a whenever i need to do anything
> related to raw devices is a performance improvment.  nor is writing
> huge kludgy initscripts or bloated daemons just so i can do:
>
> chgrp wheel /dev/somedevice
> chmod 660 /dev/somedevice
>
> and have it stick.  (past reboots)
>
> as for anyone attempting to make the silly claim that /dev has
> thousands of devices and thus incurs the evil ext2fs directory
> slowness ask them why they are not turning /usr/bin into a fake
> filesystem.
>
> [eb@plato eb]$ ls -1 /dev | wc -l
>    1222
> [eb@plato eb]$ ls -1 /usr/bin | wc -l
>    2109
> [eb@plato eb]$
>
> the only directory on my system which i can even percieve the
> slightest slowdown is /var/lib/dpkg/info, and even then its hardly
> noticable nor anything to cry about:
>
> [eb@plato eb]$ ls -1 /var/lib/dpkg/info | wc -l
>    5289
> [eb@plato eb]$
>
> better solutions to ext2 directory performance is fix the filesystem,
> reiserfs does not have this problem and i think ext3 does not either.
>
> the only other argument i ever hear is whining about device files with
> no corrosponding device, well i could care less. if i will never will
> have the device and it bothers me THAT much rm -f /dev/somedevice*.
> otherwise its nice to know exactly what permissions some hardware will
> have before installing it.  /dev is not a database of what hardware is
> installed, that belongs to /sbin/lspci and /proc (though proc is a
> hideous mess, everything except processes should have been moved to
> /kern long ago)
>
> anyway thats just my rant on the subject, if you like devfs use it,
> but leave it an OPTION so i can leave it off.  (and not an `option'
> like proc has become where you have the option to turn off and have a
> useless broken system)
>
> --
> Ethan Benson
> http://www.alaska.net/~erbenson/
>



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