kvm disk performance with different backends

Here  some results from testing I did in August 2009 on  KVM with the three different disk image drivers. First a single disk system running Ubuntu x64 9.04:

QCOW2:
/dev/vda:
Timing cached reads: 9836 MB in 2.00 seconds = 4923.22 MB/sec
Timing buffered disk reads: 1050 MB in 3.00 seconds = 349.92 MB/sec

RAW:
/dev/vda:
Timing cached reads: 10118 MB in 2.00 seconds = 5064.57 MB/sec
Timing buffered disk reads: 1054 MB in 3.00 seconds = 351.32 MB/sec

LVM
/dev/vda:
Timing cached reads: 9328 MB in 2.00 seconds = 4668.90 MB/sec
Timing buffered disk reads: 202 MB in 3.00 seconds = 67.26 MB/sec

qcow2,488M,61454,88,288839,43,61540,14,45880,57,445361,57,13550.6,99,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++
raw ,488M,54972,86,54393,16,60636,17,68490,84,442091,43,6685.1,97,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++
lvm ,488M,58248,90,62764,17,58271,19,64677,83,455263,38,7912.3,96,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++

QCOW2
Version 1.03c ------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
vm2 488M 61454 88 288839 43 61540 14 45880 57 445361 57 13551 99
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++
vm2,488M,61454,88,288839,43,61540,14,45880,57,445361,57,13550.6,99,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++

RAW

Version 1.03c ------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
vm2 488M 54972 86 54393 16 60636 17 68490 84 442091 43 6685 97
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++
vm2,488M,54972,86,54393,16,60636,17,68490,84,442091,43,6685.1,97,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++

LVM
Version 1.03c ------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
vm2 488M 58248 90 62764 17 58271 19 64677 83 455263 38 7912 96
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++
vm2,488M,58248,90,62764,17,58271,19,64677,83,455263,38,7912.3,96,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++

Then a spreadsheet with a large set of test using Ubuntu x64 9.04 host  with two ES SATA disks and LVM over raid1/md.

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