On 06/15/2010 03:58 PM, Gene Cumm wrote:> While researching another issue unrelated to Syslinux, I found some
> mildly disturbing news that affects Syslinux. As HPA stated back on
> 2009-06-04, hard drive manufacturers are pushing towards a 4096B
> (4kiB; 4k) native sector size. They're calling it "Advanced
Format
> Technology". It appears that WD (Western Digital; WDC) is the first
> with some products being released back in December and that Seagate
> just recently "jumped on the bandwagon".
>
> Seeing as HPA's mention of the 4kiB sector back on 2009-06-04 was the
> only mention I've seen and "Advanced Format" can't be
seen anywhere in
> the list archives, I felt it worthwhile to mention "it's
here", at
> least to some extent.
>
> In WD's whitepaper (PDF available by selecting language at
> http://www.wdc.com/wdproducts/library/?id=216&type=87), it does,
> however, talk about performing in-drive emulation from 512B to 4096B
> sectors and that they have a utility
> (http://www.wdc.com/en/products/advancedformat/) to "realign" for
> "performance" (still can't be certain what this really means;
> sacrifice 1/64 capacity by packing (63) 512B sectors on (8) 4096B
> sectors?).
>
> Has this been discussed at all off-list (ie IRC)? With the in-drive
> emulation, it seems like it either won't affect anything or it
won't
> affect it for now.
>
Logical sector size (as opposed to physcial sector size) is likely to
remain at 512 for at least some time. "Advanced Format" is, ahem, at
the very best a euphemism.
Realigning for performance just means changing the partitions to all be
on 4K boundaries, which is a good thing; for FAT it might also pad some
of the internal data structures to make sure the clusters are also aligned.
-hpa