Re: [PATCH 08/16 v2] pramfs: headers

[Ryan Mallon <ryan@bluewatersys.com>]

On 11/10/2010 09:15 PM, Marco Stornelli wrote:
> 2010/11/9 Geert Uytterhoeven <geert@linux-m68k.org>:
>> On Tue, Nov 9, 2010 at 21:35, Ryan Mallon <ryan@bluewatersys.com> wrote:
>>> You can still do all of those things without having a fixed endianess.
>>> You just have to have one extra step of telling the external tools what
>>> the endianess is. IMHO, it is better to have the overhead of the endian
>>> conversion in the tools since it is less costly there than an the
>>> embedded system.
>>>
>>> I'm just trying to understand why the fixed endianess rule cannot be
>>> bent for such a specialised filesystem.
>>
>> When it was decided that filesystems should be fixed-endian and support for
>> big-endian ext2 was dropped, the overhead of doing the fixed conversions was
>> deetermined negligible due to compiler optimization.
>> That was ages ago, and current embedded systems run circles around the
>> machines of those days.
>>
>> Note that this is about metadata only. Actual file contents are always just
>> byte streams.
>>
> 
> I can add that the penalties in this case are  negligible due to the
> compensation of the very fast access of the media. In addition, from
> performance point of view I'm pretty happy (you can see the some
> benchmark on the project web site).

Thanks for the explanation guys.

~Ryan

-- 
Bluewater Systems Ltd - ARM Technology Solution Centre

Ryan Mallon         		5 Amuri Park, 404 Barbadoes St
ryan@bluewatersys.com         	PO Box 13 889, Christchurch 8013
http://www.bluewatersys.com	New Zealand
Phone: +64 3 3779127		Freecall: Australia 1800 148 751
Fax:   +64 3 3779135			  USA 1800 261 2934