GPT and disk alignment

Mark Felder feld at
Wed Jun 8 04:49:55 UTC 2011

On Tue, 07 Jun 2011 22:27:24 -0500, Robert Simmons <rsimmons0 at>  

> Do all HDDs that have 4KB per LBA present themselves to the OS as
> having 512 bytes per LBA?


> What about SSDs that have 1024 bytes per LBA?

Not sure, but I do know that not all flash media have the same bytes per  
LBA internally. Some are 1K, some 4K, some even 8K. GPT is definitely the  
way to go if you want to make sure you're aligned.



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