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From: Hywel Mallett <hywel@hmallett.co.uk>
To: Ivan Voras <ivoras@freebsd.org>
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Cc: freebsd-geom@freebsd.org
Subject: Re: Filesystem replication geom proposal
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On 29 Jun 2008, at 21:48, Ivan Voras wrote:
>
> Yes, gmirror would have to grow support for "smart" resilvering,  
> probably by having a bitmap of changed blocks maintained on the  
> working drive(s) so it can only update the changed data instead of  
> whole drives (which would happen now if ggated would support  
> automatic reconnects).
>
The problem with that simplistic approach is that because write-order  
fidelity is not maintained, during the resynchronisation the slave/ 
secondary is inconsistent.