| 2020-03-02 10:03:26 |
Andrea Ieri |
description |
Pods are currently created with mem == maxmem. The consequence is that if a pod needs to subsequently be resized (which is likely to happen at some point during the life of a cloud), it will have to be stopped and started. Having a higher maxmem would allow operators to live-update ram in pods, reducing downtime. For this reason it would be great if maas allowed pods to be composed with a higher maxmem value, and possibly set it by default to something reasonable. |
Composed KVM virtual machines are currently created with mem == maxmem. The consequence is that if one of these virtual machines needs to subsequently be resized (which is likely to happen at some point during the life of a cloud), it will have to be stopped and started. Having a higher maxmem would allow operators to live-update ram in VMs, reducing downtime. For this reason it would be great if maas pods composed machines with a higher maxmem value, and possibly set it by default to something reasonable.
More specifically:
Let's say I have a KVM guest with 8GB of RAM assigned. I now realize this is too small, and I want to double its RAM to 16GB. With maxmem == mem I have to run the following:
* virsh setmaxmem <domain> <16GB_or_more> --config
* virsh setmem <domain> 16GB --config
* shutdown the VM
* virsh start <domain>
If the KVM guest had however been originally created with (for example) maxmem = 4*mem, I would be able to do the following instead and avoid a reboot:
* virsh setmem <domain> 16GB --live |
|
