> Yes. And that may be some s"synergetic" effect triggered by the > slowness. At least that is one possible explanation. Agreed. > You could try this with a dummy-cipher that does not take encryption time. > > I have not tried this myself, but hit candidates are > "ciper_null" and "ecb(ciper_null)". I have both (kernel > 2.6.30.5) They're there all right, must have overlooked them. However I haven't managed to construct a cipher spec that'll work with cryptsetup. Maybe because it takes no key ... Various tunings of the host's page cache (under /proc/sys/vm/) to make flushes less bursty didn't help much. In the meantime I've set up a dedicated kvm guest for these tests, with one encrypted and one unencrypted scratch volume. Maybe some systematic benchmarking will point somewhere. Seems a lot of people are having this problem, since ~2.6.24 at least, and it seems to get worse the slower the CPUs are, the faster the disks are. Chosing a faster cipher seems to help. Chris _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
