Decrease/Increase memory allocation of the CVM on Community Edition 1.0 (CE1)
You can attempt different memory allocations, however the lowest I was able to put it at without experiencing issues with the CVM, was 12GB.
1. ssh to root@{AHV_IP}
2. Type the following in the shell: virsh list –all
[root@NTNX-84e038f2-A ~]# virsh list --all
Id Name State
----------------------------------------------------
1 NTNX-84e038f2-A-CVM running3. Attempt to shutdown the CVM by running: virsh shutdown NTNX-84e038f2-A-CVM
[root@NTNX-84e038f2-A ~]# virsh shutdown NTNX-84e038f2-A-CVM
Domain NTNX-84e038f2-A-CVM is being shutdownIf the CVM will not shut down due to running VMs, you can shut them down nicely with this command:
for i in $(acli vm.list power_state=on | grep -v NTNX | awk 'NR!=1 {print $NF}');do acli vm.shutdown $i ; doneConfirm the power status of the VMs with this command:
acli vm.list power_state=on4. Once the CVM is offline, you can run the following commands to adjust the memory allocation
virsh setmem NTNX-84e038f2-A-CVM 12G --config
virsh setmaxmem NTNX-84e038f2-A-CVM 12G --config5. Once the new allocation is defined, start up your CVM again and verify from UI or using dominfo:
virsh start NTNX-84e038f2-A-CVM
virsh dominfo NTNX-84e038f2-A-CVMDecrease/Increase memory allocation of the CVM on Community Edition 2.0 (CE2)
As the above procedure would fail on CE2, we will use a different approach, which is as follows:
1. SSH to root@{AHV_IP}
2. Type the following to get the CVM name of which you want to change the memory:
[root@NTNX-1872f42b-A ~]# virsh list --all
Id Name State
------------------------------------------------------
1 NTNX-1872f42b-A-CVM running
2 08fe9bd1-6180-4a58-9c5a-46fb19e330f3 running
4 5ea7bae8-57da-4943-8915-13248d365505 running
5 93ca3d8a-87f1-4566-901a-7e403fcab078 running
6 42a09496-5d26-4ef4-875f-a1fc9829bddd running
10 8fe10513-5c9c-46e8-bff3-6abe14e2865a running
11 bc9675dd-8045-47c9-8991-2e83513ab593 running
12 8745b3bc-7f42-4881-b627-2548c180e09c runningMake sure to shutdown the CVM. If you are having trouble shutting it down, refer to step 3 above.
3. Now that we have the CVM name, edit the dominfo XML, by typing the following:
virsh edit NTNX-1872f42b-A-CVM4. The file will open in a vi editor, and will look as described below. I have put mine down to 18G of memory. This will be the 18874368 value below, listed at memory unit, currentMemory unit=’KiB’ and memory in cpu and memory tags.
<domain type='kvm'>
<name>NTNX-1872f42b-A-CVM</name>
<uuid>46351276-270a-4228-bda0-fa65dd41f42b</uuid>
<memory unit='KiB'>18874368</memory>
<currentMemory unit='KiB'>18874368</currentMemory>
<memoryBacking>
<hugepages/>
<nosharepages/>
</memoryBacking>
<vcpu placement='static' cpuset='0-23'>6</vcpu>
<resource>
<partition>/machine</partition>
</resource>
<os>
<type arch='x86_64' machine='pc-i440fx-rhel7.6.0' max_ram_below_4g='536870912'>hvm</type>
<boot dev='cdrom'/>
<bootmenu enable='no'/>
</os>
<features>
<acpi/>
<apic eoi='on'/>
<pae/>
</features>
<cpu mode='host-passthrough' check='none' migratable='on'>
<topology sockets='1' dies='1' cores='6' threads='1'/>
<numa>
<cell id='0' cpus='0-5' memory='18874368' unit='KiB' memAccess='shared'/>
</numa>
</cpu>
Hints: In order to edit the file, press I to insert the new values – press ESCAPE followed by :wq to write and quit the editor.
5. Confirm the changes in the dominfo and start the CVM again:
[root@NTNX-1872f42b-A ~]# virsh dominfo NTNX-1872f42b-A-CVM
Id: 1
Name: NTNX-1872f42b-A-CVM
UUID: 46351276-270a-4228-bda0-fa65dd41f42b
OS Type: hvm
State: running
CPU(s): 6
CPU time: 79411.6s
Max memory: 18874368 KiB
Used memory: 18874368 KiB
Persistent: yes
Autostart: enable
Managed save: no
Security model: selinux
Security DOI: 0
Security label: system_u:system_r:svirt_t:s0:c339,c822 (enforcing)[root@NTNX-1872f42b-A ~]# virsh start NTNX-1872f42b-A-CVM
on the ce2, the change does not survive a reboot…i’ve read that you need to make a change on the host, but i can’t find what it is
This change is indeed on the host, as the host manages the Controller VM.
Did you make sure to change memory unit, currentMemory and cell id (under cpu mode -> numa) tags? — Search for “18874368” on this page.
This is how I’ve always done it, never failed me.