From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tomasz Chmielewski <mangoo@wpkg.org>
Subject: Re: Data Deduplication with the help of an online filesystem check
Date: Tue, 28 Apr 2009 18:04:06 +0200
Message-ID: <49F728F6.6030307@wpkg.org>
References: <20090427033331.GC17677@cip.informatik.uni-erlangen.de> <1240839448.26451.13.camel@think.oraclecorp.com> <20090428155900.GA1722@cip.informatik.uni-erlangen.de>
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Cc: Chris Mason <chris.mason@oracle.com>, linux-btrfs@vger.kernel.org
To: Thomas Glanzmann <thomas@glanzmann.de>
Return-path: <linux-btrfs-owner@vger.kernel.org>
In-Reply-To: <20090428155900.GA1722@cip.informatik.uni-erlangen.de>
List-ID: <linux-btrfs.vger.kernel.org>

Thomas Glanzmann schrieb:

> 300 Gbyte of used storage of several productive VMs with the following
> Operatings systems running:
> \begin{itemize}
>         \item Red Hat Linux 32 and 64 Bit (Release 3, 4 and 5)
>         \item SuSE Linux 32 and 64 Bit (SLES 9 and 10)
>         \item Windows 2003 Std. Edition 32 Bit
>         \item Windows 2003 Enterprise Edition 64 Bit
> \end{itemize}
> \begin{tabular}{r|r|r|l}
> blocksize & Deduplicated Data \\
> \hline
> 128k      &  29.9 G \\
>  64k      &  41.3 G \\
>  32k      &  59.2 G \\
>  16k      &  82   G \\
>   8k      & 112   G \\
> \
> 
> Bottom line with 8 K blocksize you can get more than 33% of deduped data
> running a productive set of VMs.

Did you just compare checksums, or did you also compare the data "bit 
after bit" if the checksums matched?


-- 
Tomasz Chmielewski