Ext4 vs. Btrfs performance on Qubes OS installs

[Insurgo]

@rustybird

Whereas file-reflink layouts like Btrfs use loop devices, which are currently always configured (by /etc/xen/scripts/block from Xen upstream) with 512 byte logical sectors - again passed through to the VM.

So @Sven
This seems to mean that the BRTFS pool

@Insurgo

[user@dom0 ~]$ sudo qvm-pool
NAME          DRIVER
varlibqubes   file
linux-kernel  linux-kernel
vm-pool       lvm_thin

BRTFS is a qvm-pool of varlibqubes type.

@Sven

Alright, from your perspective that might be true. From my perspective I compared Qubes OS default vs. choosing Btrfs in the installer and might have chosen the thread title wrong.

I made this one change and got a substantial increase in performance. I’d like to understand and if possible have others enjoy the same benefit.

Agreed. This is important. But I would love to understand why thin-lvm pools are stuck to 512 sectors and have thin-lvm pools have maximum performance speeds (which LVM pools are the standard way, and for which wyng-backups is the only supported pool today).

As far as my understanding, LVM2 thin pool is beginning to have a bad press and people are starting to want to get away of it because of misconfiguration by default, where @Rudd-O pushes for ZFS, others push for XFS and here we push for BTRFS. I think if LVM pools and LUKS containers were configured in an optimized way, we might not all want to get out of it