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Date: Fri, 07 Aug 2009 09:51:08 -0600
From: "Chris Friesen" <cfriesen@nortel.com>
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To: Greg KH <greg@kroah.com>
CC: Al Boldi <a1426z@gawab.com>, Andi Kleen <andi@firstfloor.org>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>, linux-kernel@vger.kernel.org,
       Kay Sievers <kay.sievers@vrfy.org>, Jan Blunck <jblunck@suse.de>,
       gregkh@suse.de, Harald Hoyer <harald@redhat.com>,
       Scott James Remnant <scott@ubuntu.com>
Subject: Re: [PATCH] Driver Core: devtmpfs - kernel-maintained tmpfs-based
 /dev
References: <20090805171513.GA10443@kroah.com> <200908070703.40706.a1426z@gawab.com> <20090807042544.GA24299@kroah.com> <200908070804.08156.a1426z@gawab.com> <20090807052015.GA24615@kroah.com>
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Greg KH wrote:
> On Fri, Aug 07, 2009 at 08:04:08AM +0300, Al Boldi wrote:

>> The question is, how fast can devtmpfs get the device list from the kernel on 
>> bootup?  How much faster than udev?  How much slower than static /dev?
> 
> It's much faster than udev, and is equivalent to a static /dev with the
> exception that the group and permission settings that you are used to.
> udev then needs to come along and make those settings, but that's so
> frickin fast it's amazing.

Earlier in the thread you indicated a 0.5sec speedup over udev.  Is that
really considered "much faster"?

I do agree that it makes sense to do this, but more from an elegance
view than a performance one.

Chris