cold boot took too much time in UME

[Yu Ping]

Description:
while in testing for UME in cold boot, we found the cold boot time is 80 second. Compared with moblin boot time 60 second, this time is too long.

Reproduce Steps:
(1)count the time
(2)cold boot the machine

Expected Result:
this cold boot time is less than 60 second

[Zhao Fan (fan-zhao)]

We collected the following 2 indicators to measure the cold boot time.
total boot time: the time from pushing power button to hildon deskotp shows to user
SW boot time: the total boot time - BIOS time.

To help analyze the result, we also collects the time in different booting stage, which includes BIOS time, kernel time, service time, and X+desktop time.

Here is the data comparison of UME beta4 and moblin beta4:
                                UME_beta4 Moblin_beta4
total boot time 80s 60s
SW boot time 67s 47s

BIOS time 13s 13s
kernel time 9s 8s
service time 30s 8s
desktop time 28s 31s

We can see from the comparison that UME_beta4 boot time has 20s gap with moblin_beta4 boot time, and the gap lies in service time.

Martin Xu from moblin engineering team did a lot of optimization for moblin cold boot time, maybe he could provide some suggestions here.

[Yu Ping (ping-y-yu)]

re-test this bug in UME rc image, and the cold boot time is about 80 second. No obvious improvement