kvm disk comparison

I used bonnie++ to get some disk benchmarks.  The virtual io is supposed to be much faster than the ide emulation, so let's take a look.

virtio (loop):

Version 1.03e       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
buran.denmantire 3G  8321  27 16886  13 13128   9 30720  46 15277   2 538.5   4
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16 14308  94 +++++ +++ +++++ +++  7738  58 +++++ +++ +++++ +++
buran.denmantire.com,3G,8321,27,16886,13,13128,9,30720,46,15277,2,538.5,4,16,14308,94,+++++,+++,+++++,+++,7738,58,+++++,+++,+++++,+++

ide (loop):

Version 1.03e       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
buran.denmantire 3G  8164  12 16475   3 19955   7 45174  68 71586   6 992.4  13
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16 15543  90 +++++ +++ +++++ +++ 15183  84 +++++ +++ +++++ +++
buran.denmantire.com,3G,8164,12,16475,3,19955,7,45174,68,71586,6,992.4,13,16,15543,90,+++++,+++,+++++,+++,15183,84,+++++,+++,+++++,+++

Hmmm.  Slightly faster, yes, but not the huge increase I was expecting.  Of course, that's with loop disks.  I'll try it sometime next week with a physical partition.