Re: [dm-crypt] Advanced format (4k sector disks) and dm-crypt

[Arno Wagner <arno@wagner.name>]

On Sat, Jan 18, 2014 at 20:24:47 CET, Arno Wagner wrote:
> On Sat, Jan 18, 2014 at 15:14:29 CET, Garðar Arnarsson wrote:
> > Did a quick search but came up empty handed.
> > 
> > I'm wondering if there is anything special that needs to be passed to
> > be able to use dm-crypt (cryptsetup) with 4096 byte sector drives.
> > 
> > I know md, lvm, partitions, filesystems all need to have special
> > triggers for 4K drives (even thouh I think it's done automatically for
> > all of them nowadays) but I see no mention of dm-crypt/cryptsetup.
> 
> Do not worry. Dm-crypt uses 512B sectors, but there is only a 
> negligible performance loss. This matters far, far more on the 
> filesystem layer. If that layer does it right, dm-crypt will 
> allways process 8 x 512B at a time, as it does process exacly 
> what the uppeer layer requests. And alignment in LUKS is done
> so that 4k sectors will not be broken up for the data area.
> 
> Hence this is not a concern and that is the reason it is
> not mentioned. I think I will add an FAQ entry for this.
> 
> Arno

Just added Item 2.17 to the FAQ. 

Arno
-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
----
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