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Date: Mon, 30 Apr 2012 15:00:21 +0300
From: Yaron Sheffer <yaronf@porticor.com>
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Subject: [dm-crypt] XTS performance
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To: dm-crypt@saout.de

Hi,

Looking back at the archives, it appears that AES-XTS in dm-crypt runs 
at half the speed of AES-CBC-ESSIV: 
http://www.saout.de/pipermail/dm-crypt/2010-November/001348.html. Milan 
explained it at the time by XTS doing 2 AES operations for each 
plaintext block. But my understanding of XTS is that it is similar to 
ESSIV: 1 AES op per 16-byte block, plus 1 op for the sector.

- Did I misread the definition of XTS, and it's really 2 AES ops per 
16-byte block?

- Does anybody have more recent performance comparisons, confirming (or 
not) the performance difference?

Thanks,

     Yaron