Question for #homelab and #proxmox folks:
Is LVM thinpool write performance incredibly bad on HDD (4 disks, LVM RAID1)?
I am trying to restore a 200gb backup to a fresh thinpool and I'm at 10% after 10,000 seconds...
I have a 1.3TB restore after this... That's... not going to work...
Edit: Retrying now with the VG created across two mdadm raid1 and no replication in LVM.
@amd I've not experienced significant performance dip due to thinpool on my setup. Wouldn't have thought the slightly extra metadata of thin provisioning would cause a bit impact.
iostat -mx would be worth a look at to see if your saturating the disk IO and where.
When you say raid 1, do you mean raid 10? 4 disks in a mirror seems odd.
Is the slow IO inside a VM or on the host?
@amd hmm, but is that not writing 4 copies of the data to the underlying PVs. Which seems a more likely cause of slow performance than it being thin.
@intrbiz the new restore isn’t?
Correct. I’m not sure how to make LVM create these in raid one when restoring like this. I would have to modify it later. That was one of my reasons for making the thinpool… I could make the VG from two mdadm raids…
If this completes successfully I plan to regenerate the thinpool in raid10 and see what comes of it.
@intrbiz the thinpool was created with LVM raid1 on a VG with four PV
Slow IO is noted while the proxmox host is restoring a backup to the thinpool.