Re: general zfs/zvol question

On Tue, Feb 15, 2022 at 1:25 AM Frank Leonhardt wrote:
...

> The
> main problem is the extreme fragmentation caused by copy-on-write. If
> your data largely static (user files) it's not a big deal. If it's a
> database, with millions of random access writes to the same file, that
> file's going to be spread all over the zpool and there is nothing you
> can do to stop it.


I thought (someone else mentioned it) that fragmentation is not of contents
of files but of available free space on a ZFS pool.?


- parv



> If you're using SSDs or 128Gb of cache you may not
> notice the difference in access times, but by this stage you're not
> comparing like for like.
>
> Operating systems like Windoze are always making small writes to disks
> and IME end up fragmented in the same way a database would.
>
...