On Thu, Feb 09, 2012 at 11:19:30AM +0100, Milan Broz wrote: > On 02/09/2012 08:37 AM, Arno Wagner wrote: > >On Wed, Feb 08, 2012 at 05:55:21PM +0000, Mickael wrote: > >>Here are more tests focusing the CPU load with htop snapshot: > >> > >>with Kernel 3.x, nfsd threads are using more CPU !? > > > >This is what I suspected. You setup is already slightly > >CPU-limited when reading/writing encrypted partitions. > >Any additional CPU needed by NFS is then directly deduced > >from CPU available for encryption. > > Not sure if it help, but it would be interesting if you can try > to use patch from this thread > http://article.gmane.org/gmane.linux.kernel/1245748 > > (it can be completely unrelated though, I have no time to test > it now myself) > > BTW I will add possibility to use null cipher to cryptsetup, > just to test exactly these situations (null cipher eliminates all > crypto operations), That is a really good idea! Arno > for now, you can try it with dmsetup and > measure preformance (this should uncover if encryption is > the problem or there is some timing problem): > > (Replace DEV with your disk, note key is "-" - means empty) > > dmsetup create x --table "0 $(blockdev --getsz DEV) crypt cipher_null-ecb-null - 0 DEV 0" > > Milan > _______________________________________________ > dm-crypt mailing list > dm-crypt@xxxxxxxx > http://www.saout.de/mailman/listinfo/dm-crypt > -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@xxxxxxxxxxx GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F ---- One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision. -- Bertrand Russell _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
