[U-Boot-Users] Is ramdisk a must or not?

[Wolfgang Denk]

In message <20040202150228.41627.qmail at web15203.mail.bjs.yahoo.com> you wrote:
> 
> 1.Is ramdisk a must or not for embedded application?In

It is definitely NOT a must. There are many ways  where  to  put  the
root  filesystem.  The  ramdisk may be one of the most simple ways to
get started, but there are very few projects whereit is  the  optimal
solution.

In general, using a ramdisk is NOT optimal.

> and some web pages,they say an initrd image is needed
> for loading your SCSI module at boot time.So if I
> didn't use SCSI module,I would save the initrd
> image.Is that so?

Please don't compare things that have nothing to do with each  other.
Booting  a  general  purpose  system  is one thing (here you have one
generic kernel image which will have to work on many, many  different
hardware  configurations,  and  extensive  use of driver modules is a
must), while an embedded system is a completely different story (here
you have one fix hardware configuration and normally  you  don't  use
any modules at all).

> 2.What advantage does ramdisk have?In which situation
> should we use it?

It is easy to build and to test.

I cannot think of a situation where a ramdisk image is the  best  way
to go for embedded systems.

> ramdisk).It displayed "Application running".What does
> application refer to?Busybox or ramdisk itself?If I

Application refers to the "/bin/application" script.

> want to make my added application in ramdisk run
> automatically,how should I do?

Add it, and make sure it gets started (like by editing /etc/inittab).

Best regards,

Wolfgang Denk

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