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Date: Tue, 16 Jun 2015 08:27:51 +0200
From: Tovo Rabemanantsoa <tovo.rabemanantsoa@bordeaux.inra.fr>
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To: Btrfs BTRFS <linux-btrfs@vger.kernel.org>
Subject: Re: Bad performance with near-full FS
References: <557EC95C.8020902@bordeaux.inra.fr> <20150615132915.GM6761@twin.jikos.cz> <557EE4BF.2090908@bordeaux.inra.fr> <557EF12E.6000309@gmail.com>
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On 06/15/2015 05:37 PM, Austin S Hemmelgarn wrote:

> For almost any non-COW filesystem (ext4, XFS, JFS, etc.), 1% or 100MB
> (whichever is larger) is generally a good buffer.  On BTRFS, I would say
> at least 5% or 1.5G (again, whichever is larger; and if performance is a
> concern, go for at least 10-20%), as BTRFS is known to have some rather
> poor behavior when running very close to full.
> 
> 
I got it.
Thanks all !

T.