Re: [PATCH 08/16 v2] pramfs: headers
From: Ryan Mallon
Date: Wed Nov 10 2010 - 14:08:08 EST
On 11/10/2010 09:15 PM, Marco Stornelli wrote:
> 2010/11/9 Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>:
>> On Tue, Nov 9, 2010 at 21:35, Ryan Mallon <ryan@xxxxxxxxxxxxxxxx> 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
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