From: Justin Piszcz <jpiszcz@lucidpixels.com>
Subject: Re: EXT4 is ~2X as slow as XFS (593MB/s vs 304MB/s) for writes?
Date: Sat, 27 Feb 2010 06:09:07 -0500 (EST)
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Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org,
	Alan Piszcz <ap@solarrain.com>
To: Eric Sandeen <sandeen@redhat.com>
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On Sat, 27 Feb 2010, Justin Piszcz wrote:

> 
> 
> On Sat, 27 Feb 2010, Justin Piszcz wrote:
> 
> > 
> > 
> > On Fri, 26 Feb 2010, Eric Sandeen wrote:
> >

Hi,

I have found the same results on 2 different systems:

It seems to peak at ~350MiB/s performance on mdadm raid, whether
a RAID-5 or RAID-0 (two separate machines):

The only option I found that allows it to go from:
10737418240 bytes (11 GB) copied, 48.7335 s, 220 MB/s
to
10737418240 bytes (11 GB) copied, 30.5425 s, 352 MB/s

Is the -o nodelalloc option.

How come it is not breaking the 350MiB/s barrier is the question?

Justin.