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Date: Mon, 27 Apr 2015 17:58:04 +0200
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To: Hugo Mills <hugo@carfax.org.uk>, sri <toyours_sridhar@yahoo.co.in>,
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Subject: Re: btrfs freeze/thaw when using with LVM2
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On 27.04.2015 o 14:15, Hugo Mills wrote:
> HOWEVER, you shouldn't take LVM snapshots of a btrfs filesystem AT ALL

I'd like to add, that generally when working with LVM and BTRFS, it's 
probably a good idea to always use "device=" mount option to make it 
scan only specified devices instead of all. I'd learned that the hard 
way, when I enabled SSD caching, and got massive corruption, because 
BTRFS mixed up cached devices with cache-origin devices. Now I have 
"device=/dev/mapper/vg-home1,device=/dev/mapper/vg-home2" in mount 
options in my fstab, and I can use LVM cache without worrying that 
things will get mixed up again.