Reducing memory overhead - Proxmox on Debian Stretch

[Chris Thompson]

I realize this isn't the typical use case. Have Proxmox up and running atop a Debian Stretch install on a very low power\low ram host (Intel Cherry Trail Z8350 processor with 4G RAM). This isn't for production, but mostly a learning environment. Had to do the Proxmox install atop Debian as I had some issues with the Proxmox installer on this particular hardware, whereas Debian would install.

Thing is, without even a single VM or container running, I have ~ 800MB - 900MB of RAM utilized. Any way I can reduce this footprint? On a 4GB host, this seems like a lot of overhead. I don't have ZFS in the mix (using EXT4\LVM partitions).

Appreciate any advice in advance. I'm open to disabling services that might be unnecessary. Note that the Debian ISO I used was the latest Debian Stretch multiarch netinstall iso.

Thanks in advance...

 

[LnxBil]

I have ~ 800MB - 900MB of RAM utilized. Any way I can reduce this footprint? On a 4GB host, this seems like a lot of overhead.

How did you measure this?

 

[Chris Thompson]

How did you measure this?

Utilization for the host in the GUI, as well as top and free output (see attached\below). ).

I suspect that the fact I installed it on top of linux adds some additional overhead.

Any advice appreciated. I'm considering switching to a pure KVM solution, perhaps based on something lite like Arch. But I do like Proxmox and want to leverage the U/I. Unfortunately, I don't have much to work with on this low powered host.

 

[wolfgang]

You can disable some daemons if you do not need it.
But this is not recommended and not tested.

pve-ha-lrm
pve-ha-crm
pveproxy
pvedaemon
pve-firewall
pvebanner
pvesr.timer
pvefw-logger

with this, you can only use the cli but the memory usage is under 200MB

 

[Dark26]

I'm very interesting with the answer, i m running a cluster with 3 nodes with only 2 go de ram on each.

Which service are necessary for the webgui and for the cluster ?

 

[jim.bond.9862]

I realize this isn't the typical use case. Have Proxmox up and running atop a Debian Stretch install on a very low power\low ram host (Intel Cherry Trail Z8350 processor with 4G RAM). This isn't for production, but mostly a learning environment. Had to do the Proxmox install atop Debian as I had some issues with the Proxmox installer on this particular hardware, whereas Debian would install.

Thing is, without even a single VM or container running, I have ~ 800MB - 900MB of RAM utilized. Any way I can reduce this footprint? On a 4GB host, this seems like a lot of overhead. I don't have ZFS in the mix (using EXT4\LVM partitions).

Appreciate any advice in advance. I'm open to disabling services that might be unnecessary. Note that the Debian ISO I used was the latest Debian Stretch multiarch netinstall iso.

Thanks in advance...

IMHO, if this is not prod. System and is intended for learning the proxmox OS.
Then do not worry about the overhead just keep it in mind as you creating the VMs to be frugal with VMs ram assignment.

If however the idea is to learn AND do something useful with the box , than I would budget for a better hardware.

What is the point in running a crippled system?

 

[Chris Thompson]

You can disable some daemons if you do not need it.
But this is not recommended and not tested.

pve-ha-lrm
pve-ha-crm
pveproxy
pvedaemon
pve-firewall
pvebanner
pvesr.timer
pvefw-logger

with this, you can only use the cli but the memory usage is under 200MB

 

[Chris Thompson]

Thanks for the feedback. Disabling the GUI isn't likely something I want to do. If I was going that route, I'd just go a bare bones route with Ubuntu Server or maybe Arch and use KVM with Virt Manager. That would probably reduce the overhead.

This is a low end system and certainly I will be going with some higher end hardware in the future. It's a basic test and education system. However, I'm going to be using this just for 2-3 VM's that I need up and running in the US while I'm traveling abroad for a couple of months. Don't have the time or resources to stand anything better up at this point. That will come down the road once I'm back in the US.

What's interesting is I had a White Box custom VMware ESXi 6.7 install on this same box for some time and the memory overhead seemed less than what I'm seeing with Proxmox, which was unexpected.

 

[LnxBil]

What's interesting is I had a White Box custom VMware ESXi 6.7 install on this same box for some time and the memory overhead seemed less than what I'm seeing with Proxmox, which was unexpected.

Why was this unexpected? PVE has more features (and more enabled) than VMware, so it should be suspected that it'll use more memory :-D

As @wolfgang already wrote, there are cluster services running per default, which can be disabled and stopped on a non-cluster system.

I've been running a PVE instance on an older laptop with only 4 GB-RAM _with_ ZFS as a low-power server at home and it worked fine for years. Depends heavily on what you've planned with the machine.

 

[Chris Thompson]

Good point. Didn't consider the additional services. And it is nice to have the ability to run containers as well.
I have no need for the cluster services. What services can be disabled to reduce the memory footprint while still retaining the ability to use the web UI?
Thanks so much...

Why was this unexpected? PVE has more features (and more enabled) than VMware, so it should be suspected that it'll use more memory :-D

As @wolfgang already wrote, there are cluster services running per default, which can be disabled and stopped on a non-cluster system.

I've been running a PVE instance on an older laptop with only 4 GB-RAM _with_ ZFS as a low-power server at home and it worked fine for years. Depends heavily on what you've planned with the machine.

 

[LnxBil]

What services can be disabled to reduce the memory footprint while still retaining the ability to use the web UI?

Based on the names @wolfgang provided, pve-ha-crm does include the name cluster in the abbreviation, so I guess that one is save, but I do not know for sure.

I'd also suggest to install the zram package from Ubuntu to have compressed swap in memory for a better Linux experience on low memory systems.

 

[Chris Thompson]

I was able to disable pve-ha-lrm and pve-ha-crm with no noticeable detriments and ~ 200MB of RAM recovered. Probably will live with this and not attempt to disable anything else. Appreciate everyone's comments.
Anyone know if there will be any forthcoming Kernel updates? There are some fixes in the 4.17 and newer Kernels for this CherryTrail architecture I'm running this setup on. Just curious...

 

[LnxBil]

Anyone know if there will be any forthcoming Kernel updates?

PVE is based on Ubuntu LTS Kernels, so probably no new feature until the next incarnation.