Re: raid10 far layout outperforms offset at writing? (was: Help with chunksize on raid10 -p o3 array)

[Peter Rabbitson <rabbit+list@rabbit.us>]

Keld Jørn Simonsen wrote:
> I found this old message:
> 
>> Peter Rabbitson
>> Mon, 19 Mar 2007 06:14:38 -0800
>>
> 
> The links were not valid anymore. I wanted to see the results and 
> possibly include the results in the performance wiki page
> I would appreciate some new links here.

I apologize, I don't have the data available anymore.


> Furthermore some comments to the post: My take on o3 vs f3 is that both
> in theory and practice f3 should be much faster for sequential reading,
> as the layout is equivalent to raid0. For random reading and sequential
> and random writing f3 and o3 (and the same goes for the more normal f2
> vs o2) should be about the same, especially when a filesystem and
> its associated elevator algorithm is employed.

Yes, this is what I also concluded since I wrote this email. I am in the
process of upgrading my raid setup, and while I am at it I am leaving
5GB blank partitions at the start of all my workstations spindles, so I
can get some real testing at night. I will share my methodology with the
list before I commence testing (which should take about 20 days the way
I am planing it).

But first comes the vacation - happy holidays to you too guys.
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