KVM

Un article de Casys (Canadian Sysadmins).

Sommaire

Paravirtualisation avec KVM

Centos

Centos 5.4 intègre virtio_*, mais en modules uniquement. L'installation directement sur un disque paravirtualisé (/dev/vdX) ne pose aucun problème. (A tester: LVM detecte-t-il ces volumes ?)


Performance disque

  • Host: ubuntu 9.10 -- 2.6.31-16-server (KVM 84)
  • Guest: centos 5.4 -- 2.6.18-164.9.1.el5


Performance de référence

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
dev             10G 49637  99 192634  80 42624  24 42374  87 170460  44 383.8   2
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16 14660  78 +++++ +++ 22351 100 23758  98 +++++ +++ +++++ +++

Test 1

  • paravirtualisation(virtio_blk): non
  • lvm: oui
  • cache: oui

noop

Version  1.03       ------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
test-iosched-noo 2G 11792  39  9497   5  8273   4 39243 126 154486  41 660.2  10

anticipatory

Version  1.03       ------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
test-iosched-ant 2G 24753  58 46588  23 36259  18 36042 105 151945  37 619.1   5

deadline

Version  1.03       ------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
test-iosched-dea 2G 31880  80 43116  22 28768  15 36356  97 163062  45 673.0  10

cfq

Version  1.03       ------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
test-iosched-cfq 2G 35850  83 47429  24 34027  22 38004  84 153401  31 633.4  16


Test2

  • Paravirtualisation: oui
  • lvm: non
  • cache: oui

noop

Version  1.03       ------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                                                                                                                                     
test-iosched-noo 2G  2566   9  8915   4 17398   9 33808  75 95772  28 874.1   9                                                                                                                                     
                    ------Sequential Create------ --------Random Create--------                                                                                                                                     
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--                                                                                                                                     
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP                                                                                                                                     
                 16 14557  79 +++++ +++ +++++ +++ 21901  99 +++++ +++ +++++ +++                                                                                                                                     

anticipatory

Version  1.03       ------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
test-iosched-ant 2G 15070  45  5761   3 15402   8 32304  75 88471  26 553.4   3
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16 13104  89 +++++ +++ +++++ +++ 21800  99 +++++ +++ +++++ +++

deadline

Version  1.03       ------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
test-iosched-dea 2G 14696  42 18758  11 17366  10 32002  74 88167  26 783.5   9
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16 19849  99 +++++ +++ +++++ +++ 21605 100 +++++ +++ +++++ +++

cfq

Version  1.03       ------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
test-iosched-cfq 2G  8275  25 23525  14 13512   9 21755  54 46803  18 586.7   7
                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16 20192  99 +++++ +++ +++++ +++ 20523  95 +++++ +++ +++++ +++