Fwd: XO-1.5 slow disk writes

[Tiago Marques]

On Tue, Nov 17, 2009 at 6:05 PM, Peter Robinson <pbrobinson at gmail.com> wrote:
> On Tue, Nov 17, 2009 at 6:02 PM, Daniel Drake <dsd at laptop.org> wrote:
>> On Tue, 2009-11-17 at 18:56 +0100, Sean DALY wrote:
>>> as a former audio engineer, I was surprised recently to see a unit
>>> like the Samson R16 for sale:
>>>
>>> http://www.samsontech.com/products/productpage.cfm?prodID=2009
>>>
>>> which uses an SD Card as its main memory. 8 track linear PCM audio
>>> record, 16 track playback.
>>>
>>> Of course, it's a case of several large files not lots of little
>>> ones... but it struck me that there must be some kind of SD r/w
>>> optimization in a unit like that.
>>
>> Another possibility is that SD cards might generally work a lot better
>> than miniSD ones. At least I have a Sandisk SD card here that
>> considerably outperforms the Sandisk miniSD card in my XO-1.5.
>
> Yes, that's quite possible as well. There's all sorts of different
> speeds for the cards. I've never really seen a fast mini or micro SD
> card.

And I've also never seen an SD one. Even USB drives share the same
problem and some SSDs.

See: http://www.anandtech.com/storage/showdoc.aspx?i=3531&p=17

If you manage to find SD cards with a proper FTL with some cache, I
doubt it will be cheap. Perhaps some caching done in RAM to coalesce
writes where possible? A guy has implemented that for windows but I
can't seem to find the link.

Best regards

>
> Peter
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