On 2016-10-08 14:46, Anton Aylward wrote:
I bought some 32G micro SD cards on eBay, and on advice I check to see if they were all actually 32G.
...
I found that indeed the 32G labelled chips were actually 8G.
Wow.
There's a tool that re-writes the chip ID info and so I made sure that theses 8G chips said they were 8G.
And I got my money back.
Well, good.
FOSS wins out again.
In Windows you could simply try to write 9 GiB of data files.
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I do however have a question. Running these tests takes a lot of time. I'm wondering if there is a quicker way.
I'm wondering if there is a file system whereby the mkfs builds a FS structure all the way down to the supposed end of the media, perhaps some kind of b-tree, then the fsck verifies it actually is what it supposed to be, that if the supposed 32G was actually a 8G and writes wrapped around somehow. checking the (empty, before commuting data) tree structure would show this up and give some clue as to the where?
Ext3/ext4, writing sparse files. Actual data at the end and start, perhaps some block in the middle. -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" at Telcontar)