KVM之virsh管理虚拟机内存

调整内存

virsh setmem 命令帮助：

[root@ubuntu ~]# virsh setmem --help
  NAME
    setmem - change memory allocation

  SYNOPSIS
    setmem <domain> <size> [--config] [--live] [--current]

  DESCRIPTION
    Change the current memory allocation in the guest domain.

  OPTIONS
    [--domain] <string>  domain name, id or uuid
    [--size] <number>  new memory size, as scaled integer (default KiB)
    --config         affect next boot
    --live           affect running domain
    --current        affect current domain

实验一下，调小一台虚拟机的内存：

[root@ubuntu ~]# virsh  dominfo centos_server01
Id:             6
Name:           centos_server01
UUID:           9953497f-930f-fa61-a0dc-174f1872294e
OS Type:        hvm
State:          running
CPU(s):         2
CPU time:       6.7s
Max memory:     1048576 KiB
Used memory:    1048576 KiB
Persistent:     yes
Autostart:      disable
Managed save:   no
Security model: apparmor
Security DOI:   0
Security label: libvirt-9953497f-930f-fa61-a0dc-174f1872294e (enforcing)
[root@ubuntu ~]# virsh  setmem centos_server01 --size 524288  --live --config
[root@ubuntu ~]# virsh  dominfo centos_server01
Id:             6
Name:           centos_server01
UUID:           9953497f-930f-fa61-a0dc-174f1872294e
OS Type:        hvm
State:          running
CPU(s):         2
CPU time:       26.9s
Max memory:     1048576 KiB
Used memory:    524288 KiB
Persistent:     yes
Autostart:      disable
Managed save:   no
Security model: apparmor
Security DOI:   0
Security label: libvirt-9953497f-930f-fa61-a0dc-174f1872294e (enforcing)

设置最大内存限制

virsh setmaxmem 命令帮助：

[root@ubuntu ~]# virsh setmaxmem --help
  NAME
    setmaxmem - change maximum memory limit

  SYNOPSIS
    setmaxmem <domain> <size> [--config] [--live] [--current]

  DESCRIPTION
    Change the maximum memory allocation limit in the guest domain.

  OPTIONS
    [--domain] <string>  domain name, id or uuid
    [--size] <number>  new maximum memory size, as scaled integer (default KiB)
    --config         affect next boot
    --live           affect running domain
    --current        affect current domain

需要关闭虚拟机再配置

[root@ubuntu ~]# virsh setmaxmem centos_server01 1572864 --config
error: Unable to change MaxMemorySize
error: Requested operation is not valid: cannot resize the maximum memory on an active domain
[root@ubuntu ~]# virsh  shutdown centos_server01
Domain centos_server01 is being shutdown
[root@ubuntu ~]# virsh setmaxmem centos_server01 1572864 --config
[root@ubuntu ~]# virsh dominfo centos_server01
Id:             -
Name:           centos_server01
UUID:           9953497f-930f-fa61-a0dc-174f1872294e
OS Type:        hvm
State:          shut off
CPU(s):         2
Max memory:     1572864 KiB
Used memory:    524288 KiB
Persistent:     yes
Autostart:      disable
Managed save:   no
Security model: apparmor
Security DOI:   0

#然后现在给他加大到1G
[root@ubuntu ~]# virsh  setmem centos_server01 --size 1048576 --live --config
[root@ubuntu ~]# virsh dominfo centos_server01
Id:             5
Name:           centos_server01
UUID:           9953497f-930f-fa61-a0dc-174f1872294e
OS Type:        hvm
State:          running
CPU(s):         2
CPU time:       30.5s
Max memory:     1572864 KiB
Used memory:    1048576 KiB
Persistent:     yes
Autostart:      disable
Managed save:   no
Security model: apparmor
Security DOI:   0
Security label: libvirt-9953497f-930f-fa61-a0dc-174f1872294e (enforcing)