Re: Re: File systems in embedded devices

Re: Re: File systems in embedded devices

[Nandakumar NarayanaSwamy]

Dear David,

Thanks for your inputs.
Actually i have 8 MB flash and 32 MB RAM in my target board.
I need to create a read-only file system either in flash or RAM 
which should be able to accomodate our application which is about 
8 MB (stripped one).

Thanks again for your response.

with best regards,
Purush

On Sun, 09 Feb 2003 David Woodhouse wrote :
>On Sat, 2003-02-08 at 14:20, Nandakumar NarayanaSwamy wrote:
> > Dear All,
> >
> > We are developing a embedded device based on linux. Through 
>the
> > development phase we used NFS. But now we want to move some
> > filesystem which can be created in FLASH/RAM.
>
>Which? Flash or RAM?
>
> > Can anybody suggest me some ideas so that i can solve these
> > issues?
>
>You need to give at least _some_ indication of your requirements 
>--
>what's on your file system, what is the expected pattern of 
>access to
>it, do you require write access all the time or only occasional 
>updates
>of the whole system, etc. ?
>
>
>--
>dwmw2
>

Re: Re: File systems in embedded devices

[David Woodhouse]

I'm confused. I looked below the text of my mail which you had quoted,
but couldn't see that you'd actually added anything new in response. Did
you hit 'Send' too soon?

By the way, your mail directly to me ended up in the spam bin because it
had no References: or In-Reply-To: headers to correctly identify the
mail to which you were replying.

-- 
dwmw2

Re: Re: File systems in embedded devices

[Nandakumar NarayanaSwamy]

Dear David,

Thanks for your response.

I sent it correctly after typing the full mail. I think this is 
some problem in rediff mails itself.
Anyway these are the my requirements:

1) My application is coming around 8 MB. So need a file system 
about 12 MB to which i should be able to mount the root of the 
Linux kernel.

2) I need read-only file system.

3) Is it possible to create multiple ram disks of multiple file 
systems like CRAMFS, RAMDISK for a single kernel?

Thanks in advance,
Nanda

On Sun, 09 Feb 2003 David Woodhouse wrote :
>On Sat, 2003-02-08 at 14:20, Nandakumar NarayanaSwamy wrote:
> > Dear All,
> >
> > We are developing a embedded device based on linux. Through 
>the
> > development phase we used NFS. But now we want to move some
> > filesystem which can be created in FLASH/RAM.
>
>Which? Flash or RAM?
>
> > Can anybody suggest me some ideas so that i can solve these
> > issues?
>
>You need to give at least _some_ indication of your requirements 
>--
>what's on your file system, what is the expected pattern of 
>access to
>it, do you require write access all the time or only occasional 
>updates
>of the whole system, etc. ?
>
>
>--
>dwmw2
>

Re: Re: File systems in embedded devices

[Nandakumar NarayanaSwamy]

Dear David,

Thanks for your response.

I sent it correctly after typing the full mail. I think this is 
some problem in rediff mails itself.
Anyway these are the my requirements:

1) My application is coming around 8 MB. So need a file system 
about 12 MB to which i should be able to mount the root of the 
Linux kernel.

2) I need read-only file system.

3) Is it possible to create multiple ram disks of multiple file 
systems like CRAMFS, RAMDISK for a single kernel?

Thanks in advance,
Nanda

On Sun, 09 Feb 2003 David Woodhouse wrote :
>On Sat, 2003-02-08 at 14:20, Nandakumar NarayanaSwamy wrote:
> > Dear All,
> >
> > We are developing a embedded device based on linux. Through 
>the
> > development phase we used NFS. But now we want to move some
> > filesystem which can be created in FLASH/RAM.
>
>Which? Flash or RAM?
>
> > Can anybody suggest me some ideas so that i can solve these
> > issues?
>
>You need to give at least _some_ indication of your requirements 
>--
>what's on your file system, what is the expected pattern of 
>access to
>it, do you require write access all the time or only occasional 
>updates
>of the whole system, etc. ?
>
>
>--
>dwmw2
>

Re: Re: File systems in embedded devices

[David Woodhouse]

On Mon, 2003-02-10 at 05:48, Nandakumar NarayanaSwamy wrote:
> I sent it correctly after typing the full mail. I think this is 
> some problem in rediff mails itself.

No, I was being sarcastic. There's no text below your quotation in this
mail from you either. It's all at the top. Please don't do that.

You are still violating 
	http://www.infradead.org/~dwmw2/email.html#references
	http://www.infradead.org/~dwmw2/email.html#top-posting
	http://www.infradead.org/~dwmw2/email.html#quote-selectively
and probably also to a certain extent
	http://www.infradead.org/~dwmw2/email.html#include

> Anyway these are the my requirements:
> 
> 1) My application is coming around 8 MB. So need a file system 
> about 12 MB to which i should be able to mount the root of the 
> Linux kernel.
> 
> 2) I need read-only file system.

If you really only need it to be read-only, and assuming NOR flash, then
cramfs on a flash device sounds like a sane option. If you have NAND
flash then it's slightly more complicated -- you probably need a real
writable file system which deals with NAND but you could use it in
read-only mode.

> 3) Is it possible to create multiple ram disks of multiple file 
> systems like CRAMFS, RAMDISK for a single kernel?

Why? Where would these ramdisks be loaded from in the first place?
Wouldn't you do better to use them directly from there rather than
copying them into precious RAM?

-- 
dwmw2