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Ubuntu 11.04 boot time is 80 seconds 67 of which belong to the udevd process. Here's what dmesg shows:

[    6.534288] EXT4-fs (sda5): mounted filesystem with ordered data mode. Opts: (null)
[   73.216006] udevd[399]: starting version 175

What udevd does and is it possible to reduce the time of its work?

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The required device information is exported by the sysfs file system. For every device the kernel has detected and initialized, a directory with the device name is created. It contains attribute files with device-specific properties.

Every time a device is added or removed, the kernel sends a uevent to notify udev of the change. The udev daemon reads and parses all provided rules from the /etc/udev/rules.d/*.rules files once at start-up and keeps them in memory. If rules files are changed, added or removed, the daemon can reload the in-memory representation of all rules with the command udevadm control reload_rules. This is also done when running /etc/init.d/boot.udev reload.


To know how to optimize a boot time please see this pdf file

This also would help you

If you want to check if there is a device stoping udev use this command

udevadm trigger -v

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Unfortuantely, this user did not stock around, as this is a very good answer deserving of recognition. – hexafraction Oct 18 '12 at 20:41

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