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* DOC2k booting speed ...
@ 2004-01-26 15:05 Philippe
  2004-01-26 15:07 ` David Woodhouse
  0 siblings, 1 reply; 6+ messages in thread
From: Philippe @ 2004-01-26 15:05 UTC (permalink / raw)
  To: linux-mtd


Hi,
 
I’m using 
-          doc2000 (32MB)
-          via c3 800
-          linux kernel 2.4.22
-          mtd mtd-snapshot-20040124.tar.bz2
-          I use nftl
 
 
I have build a little system (kernel+initrd). My initrd is about 4MB
compressed (10MB uncompressed)
I have set up grub in the doc
 
When grub is booting, it takes 10 seconds to load the kernel and 35 seconds
to load the initrd.
 -> 5MB loaded : 45sec
 
When I boot from the Doc but with loading from the hard drive it takes 1
seconds to load the kernel and 2 seconds to load the initrd.
 -> 5MB loaded : 3sec
 
on the m-sys web, they say that the DOC2k should have a read rate about
1MB/s so if I’m right everything should be loaded in less than 10sec
 
If anyone has a clue 
 
Thanks
 
Philippe
 
 

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: DOC2k booting speed ...
  2004-01-26 15:05 DOC2k booting speed Philippe
@ 2004-01-26 15:07 ` David Woodhouse
  2004-01-26 16:15   ` RE : " Philippe
  0 siblings, 1 reply; 6+ messages in thread
From: David Woodhouse @ 2004-01-26 15:07 UTC (permalink / raw)
  To: Philippe; +Cc: linux-mtd

On Mon, 2004-01-26 at 16:05 +0100, Philippe wrote:
> When grub is booting, it takes 10 seconds to load the kernel and 35 seconds
> to load the initrd.
>  -> 5MB loaded : 45sec
>  
> When I boot from the Doc but with loading from the hard drive it takes 1
> seconds to load the kernel and 2 seconds to load the initrd.
>  -> 5MB loaded : 3sec

Grub's drivers are not particularly optimised. Why use an initrd rather
loaded by the bootloader, rather than having the kernel itself access
the device? That should be much faster, and wouldn't even need to whole
device to be read at startup.


-- 
dwmw2

^ permalink raw reply	[flat|nested] 6+ messages in thread

* RE : DOC2k booting speed ...
  2004-01-26 15:07 ` David Woodhouse
@ 2004-01-26 16:15   ` Philippe
  2004-01-26 16:17     ` David Woodhouse
  0 siblings, 1 reply; 6+ messages in thread
From: Philippe @ 2004-01-26 16:15 UTC (permalink / raw)
  To: linux-mtd

Hi,

Thank you for your quick answer

> Grub's drivers are not particularly optimised. Why use an initrd rather
> loaded by the bootloader, rather than having the kernel itself access
> the device? That should be much faster, and wouldn't even need to whole
> device to be read at startup.

As I cannot use JFFS2 with the DOC, I use an initrd to put the whole system
in ramdrive without having the doc mounted. 
I did it to avoid filesystem failures. 

Is there another way to 
 1) boot from the DOC, 
 2) build up the OS filesystem 
 3) umount the DOC ? -> protect filesystem in case of unexpected powerdown

I saw many things about pivot_root but didn't found any simple example to
get started.

Thank you.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: RE : DOC2k booting speed ...
  2004-01-26 16:15   ` RE : " Philippe
@ 2004-01-26 16:17     ` David Woodhouse
  2004-01-26 16:39       ` RE : " Philippe
  0 siblings, 1 reply; 6+ messages in thread
From: David Woodhouse @ 2004-01-26 16:17 UTC (permalink / raw)
  To: Philippe; +Cc: linux-mtd

On Mon, 2004-01-26 at 17:15 +0100, Philippe wrote:
> Is there another way to 
>  1) boot from the DOC, 
>  2) build up the OS filesystem 
>  3) umount the DOC ? -> protect filesystem in case of unexpected powerdown

Perhaps you could use a read-only file system on the DiskOnChip, and use
a ramfs for those areas of the file system which you need to be
writable?

If you mount a ramfs on /mnt/ramfs, you can make symlinks into it from
the 'real' file system.

-- 
dwmw2

^ permalink raw reply	[flat|nested] 6+ messages in thread

* RE : RE : DOC2k booting speed ...
  2004-01-26 16:17     ` David Woodhouse
@ 2004-01-26 16:39       ` Philippe
  2004-01-26 16:51         ` David Woodhouse
  0 siblings, 1 reply; 6+ messages in thread
From: Philippe @ 2004-01-26 16:39 UTC (permalink / raw)
  To: linux-mtd

Hi

> Perhaps you could use a read-only file system on the DiskOnChip, and use
> a ramfs for those areas of the file system which you need to be
> writable?

Well I had some troubles with the /etc/mtab....

> 
> If you mount a ramfs on /mnt/ramfs, you can make symlinks into it from
> the 'real' file system.

I'll try to see if I can do something with tmpfs/ramfs...

Thank you

> 
> --
> dwmw2

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: RE : RE : DOC2k booting speed ...
  2004-01-26 16:39       ` RE : " Philippe
@ 2004-01-26 16:51         ` David Woodhouse
  0 siblings, 0 replies; 6+ messages in thread
From: David Woodhouse @ 2004-01-26 16:51 UTC (permalink / raw)
  To: Philippe; +Cc: linux-mtd

On Mon, 2004-01-26 at 17:39 +0100, Philippe wrote:
> Well I had some troubles with the /etc/mtab....

Symlink it to /proc/mounts.

See the Familiar distribution used on the iPAQ (and others) for more
clues.

-- 
dwmw2

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2004-01-26 16:51 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2004-01-26 15:05 DOC2k booting speed Philippe
2004-01-26 15:07 ` David Woodhouse
2004-01-26 16:15   ` RE : " Philippe
2004-01-26 16:17     ` David Woodhouse
2004-01-26 16:39       ` RE : " Philippe
2004-01-26 16:51         ` David Woodhouse

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