Partition sizes

[The MaZe]

Thinking on starting a proxmox-journey on a HP T630, 16GB Ram, 240GB SSD.
Because of the somewhat limited resources i wonder what would be the recommended partition sizes.
Plan is to run Home Assistant from a VM and a couple of containers. Maybe even a mailserver if it fits...
I was first thinking about a separate partition for the HA-VM, and 1 partition for the containers, and one for HA-data,
but now thinking about keeping it simple: root, swap and 'the rest'.
Planning proxmox 8.1 what would be the recommended root-size (or does the installer do a great job on that?). Assumingly 16GB for the swap partition would be recommended. How much to NOT assign to a partition to be somewhat future-proof?
I guess all those questions are answered a thousand times already but i just cant seem to find them...

TIA,
Marc

 

[sb-jw]

I would leave out the swap partition, I would prefer to work with a swap file - it's more flexible and if in doubt you can easily vary the size. I would simply give 40 GB to the root (you can make your 16G swap file in it. Although I think 16G is a bit much) and use the rest as a datastore.

You have to estimate how you do this within your VMs based on the requirements. I'm only looking at the hypervisor here.

 

[Dunuin]

Depends on how much files you want to store. By default you get these 3 storages:
1.) swap
2.) root filesystem also used as "local" storage for files
3.) LVM-Thin pool where you can'T store files and only virtual disks of your VMs/LXCs

So choose a size for your root filesystem that fits all your files (16GB for system + XGB for files) and use the remaining space for your thin pool.
I think something like 4GB should be fine for swap. So don't want to overprovision your RAM anyway so its just for defragmenting your RAM and to prevent some spikes causing OOM.

 

[The MaZe]

I would leave out the swap partition, I would prefer to work with a swap file - it's more flexible and if in doubt you can easily vary the size. I would simply give 40 GB to the root (you can make your 16G swap file in it. Although I think 16G is a bit much) and use the rest as a datastore.

You have to estimate how you do this within your VMs based on the requirements. I'm only looking at the hypervisor here.

But wouldnt using a swap file instead of partition cause more defregmentation? And especially in root of which jeg assume a bit there won't be much writing otherwise?

 

[The MaZe]

Isnt it best practice to keep the swap size the same as your ram?

 

[The MaZe]

Depends on how much files you want to store. By default you get these 3 storages:
1.) swap
2.) root filesystem also used as "local" storage for files
3.) LVM-Thin pool where you can'T store files and only virtual disks of your VMs/LXCs

So choose a size for your root filesystem that fits all your files (16GB for system + XGB for files) and use the remaining space for your thin pool.
I think something like 4GB should be fine for swap. So don't want to overprovision your RAM anyway so its just for defragmenting your RAM and to prevent some spikes causing OOM.

what do you mean with 3.) ? And do i have to store other files then systemfiles in root?

 

[Dunuin]

Isnt it best practice to keep the swap size the same as your ram?

Depends on the use case. On a desktop PC you for example might want to hibernate the host so the whole volatile RAM has to fit in the non-volatile swap. You usually won't hibernate a server.

And do i have to store other files then systemfiles in root?

Yes. The LVM-Thin pool is a block storage for creating block devices and the pool itself got no filesystem so you can't store any files there. With the default setup the only place you can store any files is the root filesystem. And it's also not possible to shrink that thin pool later to extend the root filesystem. So you have to make a good decision when installing how big you want your root filesystem and your thin pool. Those can be set in the advanced options in the installer. See "Advanced LVM Configuration Options" paragraph in the manual: https://pve.proxmox.com/wiki/Installation

If you really want you could manually create a thin volume on that thin pool, manually format it with some filesystem, manually mount it and manually add its mountpoint as a directory storage in PVE to store some files on that thin pool. But thats nothing the webUI will support you to do.

 

[The MaZe]

And it's also not possible to shrink that thin pool later to extend the root filesystem. So you have to make a good decision when installing how big you want your root filesystem and your thin pool. Those can be set in the advanced options in the installer. See "Advanced LVM Configuration Options" paragraph in the manual: https://pve.proxmox.com/wiki/Installation

But it would be possible to extend both root and thin pool afterwards? In which case it might be wise to not use the full ssd but reserve some space for future expanding on either of those?

 

[Dunuin]

But it would be possible to extend both root and thin pool afterwards?

Yes, but it's an annoying manual process where you should know how to manage your LVM.

 

[The MaZe]

So basically i need 16Gb in root for proxmox itself, an additional 4-8Gb for the swapfile? To support storage of isos, systemupdates and so on i can use an externally attached hdd? Thus leaving the rest of the ssd (minus mentioned 16 and 4/8) for running VMs and/or containers?

 

[Dunuin]

Swap depends. When using ZFS there will be no swap (and you shouldn't put a swap file on your PVE pool. If you want swap with ZFS tell the installer to not allocate the whole space and later manually create a swap partition.
When using LVM the installer will create a swap LV.

And yes, you could store ISOs on another disk. Not sure what you mean with systemupdates. Updates and installing packages will consume space on your root filesystem so uses the same space as your PVE installation (which is a full-fledged linux that allows you to do everything that is possible with a default Debian. Its not an appliance).