readahead_early.

[Dave Jones <davej redhat com>]

Right now we're running readahead early way too late.
At a time when we've just sat doing no IO at all for 10
seconds whilst (amongst other things) we waited for a
DHCP lease.   We're also running it at a time when
we're competing for disk bandwidth with other processes.
The result is that disabling the service completely shows
no change in boot time at all.
http://www.codemonkey.org.uk/junk/bootchart-before.png

Moving the readahead_early service to start really early
wins back 4 seconds of boot up time.
http://www.codemonkey.org.uk/junk/bootchart-after.png

Any reason not to change this for F8 ?

Note in the 'after' png that there's now a segment
of no IO occuring between 31s and 33s. Maybe moving
the later readahead service slightly earlier will provide
additional wins.

	Dave

-- 
http://www.codemonkey.org.uk