Re: [dm-devel] dm_crypt: very low performance of random IO operations

[Milan Broz <mbroz redhat com>]

On 09/03/2010 10:28 AM, Yakov Hrebtov wrote:
> I'm experirncing problems with performance of random IO operations of 
> dm_crypt-encrypted devices.
> Sequential IO is good (using AES-NI gives almost no difference comparing with 
> unencrypted device), but random IO is poor comparing with unencrypted devices.

Just info for the list - this mail is duplicate of
https://bugzilla.kernel.org/show_bug.cgi?id=17892
so let's use this BZ to track it.

I have some ideas how to improve it, but the change must follow patches which
are currently waiting for upstream inclusion.
(Actually the per-cpu thread patches helps in this case too as side effect.)

Milan