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On Fri, Jul 08, 2005 at 10:12:52AM -0700, Greg KH wrote: |
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> On Thu, Jul 07, 2005 at 10:18:12AM -0400, Chris Gianelloni wrote: |
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> > On Wed, 2005-07-06 at 15:46 -0700, Greg KH wrote: |
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> > > To start with, the 061 version of udev offers a big memory savings if |
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> > > you use the "default" kernel name of a device[3]. If you do that, it does |
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> > > not create a file in its database in /dev/.udevdb/ |
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> > |
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> > So if we were to switch to udev 061 in genkernel, it would shrink memory |
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> > usage in our initrd/initramfs, provided we made everything use the LSB |
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> > device names/nodes, versus the devfs ones, correct? |
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> |
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> Not in the initrd/initramfs, but in the tmpfs partition that udev uses |
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> to create the /dev entries. Well, I guess you could say the |
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> "initrd/initramfs" if that is where udev is mounted on early startup (I |
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> haven't looked at how genkernel does this in a long time, sorry.) |
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> |
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> And yes, the memory savings is there, if we use the LSB names only vs |
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> the devfs name and the symlink like we currently do. |
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> |
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> To see this, look at how much space /dev/.udevdb/ takes up right now |
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> with 062 udev. Then change the following rules in |
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> /etc/udev/rules.d/50-udev.rules with the diff at the end of this email. |
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> Then reboot and look at the size of the /dev/.udevdb/ directory again. |
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> I think you will notice a huge space savings. |
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|
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<snip> |
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|
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Ok, 064-r1 version of udev does this for tty and console devices. The |
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old devfs names are now gone. Because of this, and some other config |
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file tweaks, starting udev now only takes .5 seconds on my old, slow |
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laptop, instead of 5 seconds. Hopefully others will also see such an |
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increase. |
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|
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Now to implement the persistent block device names that we showed |
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everyone at OLS... |
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|
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thanks, |
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|
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greg k-h |
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-- |
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