On 13.11.2010, 00:25 Mathias Krause wrote: > On 12.11.2010, 08:34 Huang Ying wrote: > On Fri, 2010-11-12 at 15:30 +0800, Mathias Krause wrote: >>> On 12.11.2010, 01:33 Huang Ying wrote: >>>> Why the improvement of ECB is so small? I can not understand it. It >>>> should be as big as CBC. >>> >>> I don't know why the ECB variant is so slow compared to the other variants. >>> But it is so even for the current x86-64 version. See the above values for >>> "x86-64 (old)". I setup dm-crypt for this test like this: >>> # cryptsetup -c aes-ecb-plain -d /dev/urandom create cfs /dev/loop0 >>> >>> What where the numbers you measured in your tests while developing the >>> x86-64 version? >> >> Can't remember the number. Do you have interest to dig into the issue? > > I looked at /proc/crypto while doing the tests again and noticed that ECB > isn't handled using cryptd, while all other modes, e.g. CBC and CTR, are. > The reason for that seems to be that for ECB, and only for ECB, the kernel > is using the synchronous block algorithm instead of the asynchronous one. > So the question is: Why is the ECB variant handled using the synchronous > cipher -- because of the missing iv handling in this mode? Herbert, any idea why this is the case? Regards, Mathias -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
