On Sat, Jul 11, 2015 at 10:15:52AM +0200, Martin Willi wrote:

quoted

If you're going to use sec you need to use at least 10 in order
for it to be meaningful as shorter values often result in bogus
numbers.

Ok, I'll use sec=10 in v2. There is no fundamental difference compared
to sec=1 (except for very short blocks):

Thanks.

Yes, another extreme:

testing speed of cbc(aes) (cbc(aes-aesni)) decryption
test 0 (128 bit key, 16 byte blocks): 1 operation in 593 cycles (16 bytes)
test 1 (128 bit key, 64 byte blocks): 1 operation in 1589 cycles (64 bytes)
test 2 (128 bit key, 256 byte blocks): 1 operation in 5311 cycles (256 bytes)
test 3 (128 bit key, 1024 byte blocks): 1 operation in 20666 cycles (1024 bytes)
test 4 (128 bit key, 8192 byte blocks): 1 operation in 161483 cycles (8192 bytes)
test 5 (192 bit key, 16 byte blocks): 1 operation in 593 cycles (16 bytes)
test 6 (192 bit key, 64 byte blocks): 1 operation in 1659 cycles (64 bytes)
test 7 (192 bit key, 256 byte blocks): 1 operation in 5609 cycles (256 bytes)
test 8 (192 bit key, 1024 byte blocks): 1 operation in 21568 cycles (1024 bytes)
test 9 (192 bit key, 8192 byte blocks): 1 operation in 172484 cycles (8192 bytes)
test 10 (256 bit key, 16 byte blocks): 1 operation in 612 cycles (16 bytes)
test 11 (256 bit key, 64 byte blocks): 1 operation in 1687 cycles (64 bytes)
test 12 (256 bit key, 256 byte blocks): 1 operation in 5836 cycles (256 bytes)
test 13 (256 bit key, 1024 byte blocks): 1 operation in 22400 cycles (1024 bytes)
test 14 (256 bit key, 8192 byte blocks): 1 operation in 177799 cycles (8192 bytes)

testing speed of cbc(aes) (cbc(aes-aesni)) decryption
test 0 (128 bit key, 16 byte blocks): 1 operation in 1130 cycles (16 bytes)
test 1 (128 bit key, 64 byte blocks): 1 operation in 3002 cycles (64 bytes)
test 2 (128 bit key, 256 byte blocks): 1 operation in 10135 cycles (256 bytes)
test 3 (128 bit key, 1024 byte blocks): 1 operation in 39911 cycles (1024 bytes)
test 4 (128 bit key, 8192 byte blocks): 1 operation in 308130 cycles (8192 bytes)
test 5 (192 bit key, 16 byte blocks): 1 operation in 1151 cycles (16 bytes)
test 6 (192 bit key, 64 byte blocks): 1 operation in 3096 cycles (64 bytes)
test 7 (192 bit key, 256 byte blocks): 1 operation in 11486 cycles (256 bytes)
test 8 (192 bit key, 1024 byte blocks): 1 operation in 42155 cycles (1024 bytes)
test 9 (192 bit key, 8192 byte blocks): 1 operation in 328148 cycles (8192 bytes)
test 10 (256 bit key, 16 byte blocks): 1 operation in 1186 cycles (16 bytes)
test 11 (256 bit key, 64 byte blocks): 1 operation in 3260 cycles (64 bytes)
test 12 (256 bit key, 256 byte blocks): 1 operation in 11909 cycles (256 bytes)
test 13 (256 bit key, 1024 byte blocks): 1 operation in 44794 cycles (1024 bytes)
test 14 (256 bit key, 8192 byte blocks): 1 operation in 325349 cycles (8192 bytes)

Weird.  I don't see this variance with tcrypt mode=200 at all.
I do however see it with mode=500 but that's probably just telling
us that the async tcrypt code path is buggy.

It'd be good if we can figure out what's going on here.

Cheers,
-- 
Email: Herbert Xu [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
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