quick boot

[Stephane Hockenhull]

just an idea/theory


what if the default OS would do the boot process at 750Mhz (150% default speed) then switch back to 500Mhz when booted ?


high clocks are a waste when idling but it could actually save battery on boot if the CPU is the bottleneck at boot time.


the LCD, memory, gfx, wifi, etc, all that have a (mostly) constant power drain so faster boot could consume less in total.


of course if the NAND is the bottleneck it wont change much but I doubt that's the case, its likely slow from a lot of shell scripts and dynamic linking.


even if the total boot power usage stays roughly the same (higher power drain during a shorter time) it'll still be a win on boot time.


sorry if this has already been proposed, might have missed it.

 

[Vitel]

I patched my kernel to boot at 1Ghz. It cuts boot time in half.

 

[myownlittlworld]

Does it boot using goal-based (init-ng) booting? Or does it use the old-fashioned System-V boot method? I've heard the init-ng style booting also cuts boot time in half.

 

[Stephane Hockenhull]

I patched my kernel to boot at 1Ghz. It cuts boot time in half.

if that proves stable enough it'd be good to implement it standard, maybe 800Mhz just to be sure.


its good marketing to have a fast boot time, its the first impression people get of the working machine.


also, a 5 second blank non-animated screen is much faster than a 3 seconds animated (or text-scrolling) loading screen psychologically


I've done the test many times with unaware guinea pigs, told them I sped up the loading when I just blanked the screen or removed/slowed the loading animation.


human time is very subjective, if nothing's there to give us a time-base we can't measure time unless we're actively trying.

 

[second exodous]

How long dose it take to boot right now? If it is horrendously slow I'd give a kernel patch a try.

 

[Eridger]

I patched my kernel to boot at 1Ghz. It cuts boot time in half.

How would one do that?

 

[Vitel]

I patched my kernel to boot at 1Ghz. It cuts boot time in half.

How would one do that?

diff -ur linux-2.6.27-pandora-r1/drivers/misc/pandora.c linux-2.6.27-pandora-r1.oc/drivers/misc/pandora.c

--- linux-2.6.27-pandora-r1/drivers/misc/pandora.c	2011-02-25 14:20:26.446667864 +0300

+++ linux-2.6.27-pandora-r1.oc/drivers/misc/pandora.c	2011-02-25 14:19:41.033334150 +0300

@@ -24,7 +24,7 @@

 #define PND_PROC_CPUMHZ		"pandora/cpu_mhz_max"

 #define PND_PROC_CPUOPP		"pandora/cpu_opp_max"


-static int max_allowed_opp = 3; /* 3 on ED's request */

+static int max_allowed_opp = 5; /* WARNING!!! This WILL reduce the lifetime of your Pandora. */

 static int opp;


 static void set_opp(int nopp)

@@ -252,7 +252,7 @@


 static int pndctrl_init(void)

 {

-	opp = 1; /* Safest assumption for the delay */

+	set_fclk(1000);

 	opp = mhz2opp(get_fclk());


 	proc_create_rw(PND_PROC_CPUMHZ, NULL, cpu_clk_read, cpu_clk_write);

# /etc/conf.d/local.start


# This is a good place to load any misc programs

# on startup (use &>/dev/null to hide output)


echo 500 > /proc/pandora/cpu_mhz_max

 

[jottt]

How long dose it take to boot right now? If it is horrendously slow I'd give a kernel patch a try.

To quote myself from the other thread:


From flicking the switch to fully loaded XFCE (autologin).


56 seconds @ 500 MHz


41 seconds @ 1050 Mhz


15 seconds in both cases until the loading screen of Angström, so loads of time seems to be wasted by the bootloader alone. The OS itself is pretty quick (41/26).