Re: Profile conversion - unexpected large allocation on target profile during conversion

[Pedro Macedo <pmacedo@pmacedo.com>]

On 2024-05-30 2:36 PM, Pedro Macedo wrote:
> Is this over-allocation during conversion expected or known? This is 
> on kernel 6.8.9; I only really noticed this because one of the 
> filesystems failed the conversion with ENOSPC even though there should 
> be plenty of space. For now I'm working around the ENOSPC issue on the 
> smaller array by using a loop with dconvert=raid6,limit=100 followed 
> by a 30s sleep.

And to add to the oddness found on this conversion: the workaround now 
hit ENOSPC, even though technically it should be possible as I have >4 
disks with free space (but only 3 disks with equal amounts of free 
space, which I'm guessing is why ENOSPC is being triggered):

Unallocated:
    /dev/mapper/evg--1                   0.00GiB
    /dev/mapper/evg--2                   0.00GiB
    /dev/mapper/evg--3                   0.00GiB
    /dev/mapper/evg--4                   0.00GiB
    /dev/mapper/evg--5                   0.43GiB
    /dev/mapper/evg--6                 51.95GiB
    /dev/mapper/evg--7               127.95GiB
    /dev/mapper/evg--8               127.95GiB
    /dev/mapper/evg--9               127.95GiB
    /dev/mapper/evg--10               95.92GiB
    /dev/mapper/evg--11             100.95GiB
    /dev/mapper/evg--12             105.95GiB
    /dev/mapper/evg--13               33.92GiB
    /dev/mapper/evg--14                 0.00GiB
    /dev/mapper/evg--15                 0.00GiB


However, if I now run a balance with -dprofiles=single, I can clearly 
see data being converted between to raid6 with no errors, which is extra 
confusing - different code path being used perhaps?


Thanks,

Pedro Macedo