Collection of benchmarks on RAID5,6 and 10

Collection of benchmarks on RAID5,6 and 10

[Jon Nelson]

Some of you may be interested in a a big blog article I wrote on
raid5,6 and 10 performance, primarily comparing various chunk sizes
and the impact they made.
I did get some interesting (to me) results, and have some unanswered questions.

I also re-did the tests using deadline and anticipatory (and noop is
planned) and will add another entry comparing those results to cfq,
which is what I used above.

http://pycurious.blogspot.com/



-- 
Jon

Re: Collection of benchmarks on RAID5,6 and 10

[Justin Piszcz]

On Fri, 11 Jul 2008, Jon Nelson wrote:

> Some of you may be interested in a a big blog article I wrote on
> raid5,6 and 10 performance, primarily comparing various chunk sizes
> and the impact they made.
> I did get some interesting (to me) results, and have some unanswered questions.
>
> I also re-did the tests using deadline and anticipatory (and noop is
> planned) and will add another entry comparing those results to cfq,
> which is what I used above.
>
> http://pycurious.blogspot.com/

Nice benchmarks, what did you use to make the graphs?

Also, for all of your RAID configuration/systems, what do you use for 
your servers/stability after benchmarking multiple configurations?

Justin.

Re: Collection of benchmarks on RAID5,6 and 10

[Keld Jørn Simonsen]

On Fri, Jul 11, 2008 at 09:22:10AM -0500, Jon Nelson wrote:
> Some of you may be interested in a a big blog article I wrote on
> raid5,6 and 10 performance, primarily comparing various chunk sizes
> and the impact they made.
> I did get some interesting (to me) results, and have some unanswered questions.

Could you summarize the interesting results?


> I also re-did the tests using deadline and anticipatory (and noop is
> planned) and will add another entry comparing those results to cfq,
> which is what I used above.
> 
> http://pycurious.blogspot.com/

Thanks, Jon!

I added a reference to this on the wiki.

best regards
keld

Re: Collection of benchmarks on RAID5,6 and 10

[Jon Nelson]

>> http://pycurious.blogspot.com/
>
> Nice benchmarks, what did you use to make the graphs?

Thanks! I used flot (a jQuery plugin).
However, I've redone the code that creates the graphs and have
switched to google charts.
You can see a preview here:

http://www.jamponi.net/more_raid/graphs.html

I'll be revising that post to use the new graphs (unless people
holler) and to include a 2048 chunk size as per Neil's suggestion.

A future installment will show the effects of the various schedulers
(you can see the graphs for that in the link above), and yet another
installment may show filesystems over raid (and possibly filesystems
over lvm over raid).

> Also, for all of your RAID configuration/systems, what do you use for your
> servers/stability after benchmarking multiple configurations?

I'm using raid10,f2 right now but I may switch to raid6. I was using
raid5 previously. One big difference between the benchmarks and my
system is that I am using 3 drives and the benchmarks show 4.

-- 
Jon

Re: Collection of benchmarks on RAID5,6 and 10

[Jon Nelson]

I made some significant revisions to the entry to include each of the
four IO schedulers:

cfq (what I originally used), anticipatory, deadline, and noop,

removed the 128K chunk size and added 2048K (at Neil Brown's
suggestion), and re-did the graphs using google charts.

If anybody has any trouble viewing it please contact me OFF-LIST or
add a comment to the blog.
I actively welcome comments and suggestions.

See http://pycurious.blogspot.com/

-- 
Jon