Re: eMMC low write speed

From: Timo Kokkonen
Date: Fri Sep 23 2011 - 10:18:00 EST


On 09/23/11 06:03, Praveen G K wrote:
> Hi Qiang,
>
>
> On Thu, Sep 22, 2011 at 7:16 PM, Qiang LIU <godliuqiang@xxxxxxxxx> wrote:
>> Hi,
>>
>> I suggest you change another eMMC card or try SDHC card. It seems like
>> a card issue.
>
> Thanks for the response. So, do you think this has nothing to do with
> the caching or any such issues, since it is only every 63rd and 64th
> transfer causing this issue?

It is very much possible that the card itself does something internally
on every 63rd or 64th transfer. Such as wear leveling management on the
nand or perhaps some copy-on-write operations if the transfers are not
taking place in contiguous blocks.

As suggested above, you could try with another eMMC or SDCH card if it
makes a different (if possible).

-Timo
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