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From: Russell Coker <russell@coker.com.au>
To: Martin <m_btrfs@ml1.co.uk>
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Subject: Re: Btrfs filesystem freezing during snapshots
Date: Tue, 27 May 2014 02:19:47 +1000
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On Mon, 26 May 2014 16:20:55 Martin wrote:
> That looks to be running on top of drbd which will add a network write
> overhead (unless you are dangerously running asynchronously!). Hence you
> will see IO speed related limits a little sooner...

http://etbe.coker.com.au/2012/01/05/drbd-benchmarking/

Last time I did DRBD performance testing I found that the synchronous option 
was FASTER.  My theory is that no-one does much work on the options that 
aren't recommended.
 
-- 
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