Re: jffs2 and kernel config for SDHC Memory Cards

From: Thanasis
Date: Fri Mar 06 2009 - 15:24:40 EST


on 03/06/2009 08:24 PM Sitsofe Wheeler wrote the following:
> On Fri, Mar 06, 2009 at 03:56:01PM +0200, Thanasis wrote:
>> on 03/06/2009 03:39 PM Thanasis wrote the following:
>>> I want to use two of these Transcendʼs Class 6 SDHC (SD High-Capacity)
>>> Memory Cards,
>>> http://www.transcendusa.com/Products/ModDetail.asp?ModNo=147&LangNo=0&Func1No=1&Func2No=13
>>> as part of the filesystem in a netbook (Acer A110L), will mount /home on
>>> one, and /tmp and /var on the other.
>
>> Let me rephrase my questions in order to be clearer:
>> Q1: In order to achieve wear leveling should I format them as jffs2?
>
> This probably won't be very effective as you are already past the
> anecdotal size recommended for jffs2 partitions (I've heard rumours that
> it is best suited to filesystems that are less than 64Mbytes and another
> that says less than 1Gbyte). Additionally you are not providing direct
> access to the raw flash (see
> http://linux-mtd.infradead.org/faq/jffs2.html#L_stick_jffs2 ).
> Performance is probably not gong to be very good.
>
>> Q2: In order to achieve wear leveling, any specific options I should
>> enable in kernel (2.6.28) configuration?
>
> You will be wear levelled by the hardware anyway as the hardware only
> provides a block device interface and you don't have access to the raw
> flash.
>
> ccing Dave Woodhouse as he is the JFFS2 creator.
>
OK. I believe I should stick to ext2, right?
Thanks ;-)
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