Re: Orion... should we believe what we see?

See http://kevinclosson.wordpress.com/2012/02/06/introducing-slob-the-silly-little-oracle-benchmark/

Kevin's blog should be in your list of RSS feeds if it isn't already!

Cheers,

Phil

On 25 Feb 2013, at 00:34, "Tornblad, John" <JTornblad_at_emdeon.com> wrote:

> We are seeing wildy varying performance in an Orion run meant to simulate a DW workload (large sequential 1MB reads).
>
> The output below seems to be "red flags" all over:
> a) Wildly varying results, even counterintuitive results (more concurrent reads = less throughput)
> b) Latency on the first test (1 concurrent read at a time) showed 34 IOs at a 1-2 sec latency
> c) In other tests, smaller reads (128KB) seem to perform better but have only yielded a maximum of ~1300 MB/sec
>
> Trying to employ some "USE" (utilization/saturation/errors) methodology but this is time consuming. There is some skepticism of Orion's reliability in our shop. Problem statement: we believe this frame should be producing closer to 2300 MB/sec bandwidth on large sequential IOs.
>
> Any comments regarding weirdness (or normality?) of these results, steps to take next, observations would be greatly appreciated.
>
> Orion's documentation is a little scant and not many (any?) metalink notes regarding effectively using it. I've listened to Alex Gorbachev talk about Orion a couple of times but need more input on what to do or think when "things don't go right".
>
> -

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