Software raid VS hardware raid

[Mark Felder]

On Tue, 29 Jan 2013 08:57:31 -0600, Warren Block <wblock at wonkity.com>  
wrote:

> As far a gmirror is concerned, yes, drives can be removed and new drives  
> inserted while the mirror is running.  Hot swap is more of an issue with  
> the hardware.  I have not tried it with SATA drives, although I think it  
> should work.
>  The Handbook chapter on gmirror talks about the problems with GPT and  
> GEOM metadata.  In short: right now, they conflict.  It's possible to  
> mirror GPT partitions, but be aware that if you mirror more than one  
> partition on a drive, a rebuild after replacing a drive could thrash the  
> heads as mirrors are rebuilt simultaneously.
>   
> http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/geom-mirror.html

Why isn't gmirror more intelligent? I hate to use Linux as an example, but  
mdadm won't simultaneously rebuild multiple RAID sets if they use the same  
physical providers to prevent this. Could this be added as a feature? Even  
a sysctl toggle?