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Date: Tue, 25 Mar 2014 14:57:57 +0100
From: Xavier Nicollet <nicollet@jeru.org>
To: Martin <m_btrfs@ml1.co.uk>
Cc: linux-btrfs@vger.kernel.org
Subject: Re: How to debug very very slow file delete? (btrfs on md-raid5)
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Le 25 mars 2014 à 12:13, Martin a écrit:
> On 25/03/14 01:49, Marc MERLIN wrote:
> > It took 18H to rm it in 3 tries:

> And is not *the 512kByte raid chunk* going to give you horrendous write
> amplification?! For example, rm updates a few bytes in one 4kByte
> metadata block and the system has to then do a read-modify-write on
> 512kBytes...

My question would be naive, but would it be possible to have a syscall or something to do 
a fast "rm -rf" or du ?

I think ceph might have the later actually.

-- 
Xavier Nicollet