Re: ZFS pool balance and performance

> On Aug 24, 2025, at 13:36, Frank Leonhardt <freebsd-doc@fjl.co.uk> wrote:
>> 
>> 
>> Yeah, google search suggested there isn’t any way to rebalance. Is there
>> a way I can identify which vdev files are on? If so, I could delete some
>> files that are principally on raidz1-1, which would help some.
>> 
> 
> My understanding is that files may be stored across all vdevs. I don't remember there being any restriction that says a file should be on exactly one vdev; it kind of defeats the point.


Yes, I believe the same.  I was just wondering if there was a way to find
out if perhaps some files had a larger portion of their blocks on one vdev
or the other.  The AI-summarized google search about that suggests I can
use zdb -dddd to get data from which I can extract that, but I haven’t
tried it yet so don’t know if it’s valid.

> I'm rather hoping someone working on current ZFS internals will come along and give a few definitive answers here!

Yup.  Thanks.

     - Chris