Proxmox, ZFS, Trim and SSD

[Sjaak69]

I would like to install Proxmox on a ZFS (raid1) pool. The SSDs are cheap SSDs and not high end server SSDs.

As I understand from others and from this information (open-zfs.org wiki, can't post links)
ZFS on linux does not support TRIM yet.

I read many people using my suggested setup with ZFS mirror on a SSD. But do does people have a workaround to enable some kind of TRIM support? Because otherwise SSD lifetime will decrease heavily, right?

Furthermore, since ZFS is available in the installer of Proxmox, shouldn't be there any warning before installation on SSD that ZoL can break down a SSD very fast because of missing TRIM support?

 

[Rhinox]

It's a pitty ZoL does not support trim, but it is not a "must"! Sure trim is good, and having trim is better than not having, but "garbage collection" on modern SSDs can live without it (albeit not so effectively). Sometimes you can find that additional "user-level" over-provisioning might help, but even that is not necessary now...

 

[LnxBil]

You can start off with a blkdiscard on the SSDs before installing, but as @Rhinox already explained, TRIM is not necessary. The life expectancy depends heavily on the internal structure of the SSD and how writes are handled with respect to write amplification. I tried a consumer SSD once with PVE and ZFS and it wear out over 15% in one month. I'm running a full SSD server with enterprise grade SSDs for over 4 years and are still on 99% health. If you're lucky, your life expectancy is somewhere in between these two measurements.