Re: ORACLE on Linux - IO bottleneck

Noons wrote:
>
> If anyone knows of detailed benchmark data that lead to the
> io elevators being developed in kernel 2.4, I'd love to have a look
> at them. So far, I've been unable to create any test case where
> they would be of a definite advantage.
>

Hi Noons,
personally I have never played with the elvtune so I'm really interested in your result.
Have you published something?

I tested the four 2.6 I/O schedulers (and their parameters) and the difference in performance are quite relevant.

Benchmarks on the use of these schedulers are easy to spot out.

I'm posting what was written on the linux kernel developer mailing list: http://www.cs.rice.edu/~ssiyer/r/antsched/shines.html http://www.cs.rice.edu/~ssiyer/r/antsched/antio.html and linux symposium (with a little bit of theory): http://www.linuxsymposium.org/proceedings/reprints/Reprint-Axboe-OLS2004.pdf http://www.linuxsymposium.org/proceedings/reprints/Reprint-Pratt-OLS2004.pdf

This can be considered "dated" but in my opinion a very good reading on the linux block layer and on what the elevator can achieve is "Improving Linux Block I/O for Enterprise Workloads".

Regards

-- 
Fabrizio Magni

fabrizio.magni_at_mycontinent.com

replace mycontinent with europe