:Noob: Question about Proxmox setup with either SSD or HDD

[Fckitdudeletsgobowling]

Hello!

Extreme newbie so be kind!

I have one SSD and a few HDDs. I'm not planning to do something fancy at start, more just to tinker and learn with proxmox (jellyfin, pihole etc).

My question is this... Should I install the Proxmox to the SSD as the boot disk or should I use the HDD for that and leave the SSD for VMS and such? Just thinking if it will be alot of wear and tear on the ssd?

Thank you!

 

[Falk R.]

Hello,

it depends on the file system. If you simply build an LVM, the SSDs will be fine, with ZFS the SSDs are quickly gone.

Furthermore is interssant whether you want to use a software raid or hardware raid.

 

[Dunuin]

Basically HDDs are bad as a VM storage because they can't handle all the IOPS. For the wear of SSDs it really depends on your workload. LVM with mostly async writes should be fine and shouldn't result in much wear. Using ZFS or sync writes will result in alot of write amplification.
Some examples I measured here:

You write 1 GB of data inside a VM:
1.) with 4K async random writes on LVM thin it will write 3,28 GB
2.) with 4K sync random writes on LVM thin it will write 8,41 GB
3.) with 4K async random writes on ZFS mirror it will write 5,44 GB
4.) with 4K sync random writes on ZFS mirror it will write 56,84 GB

So you always got some write amplification but how much really depends on your workload and filesystems. If you got a SSD that is rated for 300 TBW and you use ZFS with 4K sync writes the SSD might die after just writing 5,28 TB (300 TBW / 56,84 write amplification factor) of data inside a VM.

So if you don't got multiple durable enterprise SSDs you better use LVM thin.

 

[Fckitdudeletsgobowling]

Thank you for your replies!

I will be installing proxmox on a local HDD LVM and use the SSD for VMs then.

 

[Dunuin]

And PVE will run fine with just 16GB, so if you want to save some electricity you can also only use that one SSD for everything (and maybe one HDD as a PBS datastore for backups).