@Danp
The failed backup from last weekend left an orphaned disk and a disk connected to the control domain behind which I removed.
I tried a couple of backups today, all worked finde, including XO. However, while 4 Linux-VMs coalesced after a few minutes, one failed. So it is not limited to Windows VMs.
Usually, I get "Exception unexpected bump in size" for the windows VMs, so it might be a different issue here.
There is nothing special about the affected VM. Ubuntu 22.04 LTS, almost no CPU or IO load.
Apr 26 11:31:33 xen002 SMGC: [18314] Removed leaf-coalesce from 37d94ab0[VHD](25.000G/479.051M/25.055G|a)
Apr 26 11:31:33 xen002 SMGC: [18314] *~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*
Apr 26 11:31:33 xen002 SMGC: [18314] ***********************
Apr 26 11:31:33 xen002 SMGC: [18314] * E X C E P T I O N *
Apr 26 11:31:33 xen002 SMGC: [18314] ***********************
Apr 26 11:31:33 xen002 SMGC: [18314] leaf-coalesce: EXCEPTION <class 'util.SMException'>, VDI 37d94ab0-9722-4447-b459-814afa8ba24a could not be coalesced
Apr 26 11:31:33 xen002 SMGC: [18314] File "/opt/xensource/sm/cleanup.py", line 1774, in coalesceLeaf
Apr 26 11:31:33 xen002 SMGC: [18314] self._coalesceLeaf(vdi)
Apr 26 11:31:33 xen002 SMGC: [18314] File "/opt/xensource/sm/cleanup.py", line 2053, in _coalesceLeaf
Apr 26 11:31:33 xen002 SMGC: [18314] .format(uuid=vdi.uuid))
Apr 26 11:31:33 xen002 SMGC: [18314]