Am 27.11.22 um 23:05 schrieb Wol:
On 27/11/2022 18:21, Reindl Harald wrote:
If the array is 99% full, MD or ZFS/BTRFS have
same behaviour, in terms of reliability.
If the array is 0% full, as well
you completly miss the point!
if your mdadm-array is built with 6 TB drivres wehn you replace a
drive you need to sync 6 TB no matter if 10 MB or 5 TB are actually used
And you are also completely missing the point!
When mdadm creates an array - IF IT SUPPORTED TRIM - you could tell it
"this is a blank array, don't bother initialising it". So it would
initialise an internal bitmap to say "all these stripes are empty"
you could - but it don't
tldr - there is no reason why mdadm couldn't implement trim, and if it
did, then it would know how much of the array needed to be sync'd and
how much didn't need bothering with
who the hell cares about what it *could*?
it simply don't and that's state of play
that's the difference between a filesystem on top of mdadm versus a
filesystem which implements RAID on it's own
that's the whole point: what things actually do
