Re: Multi CPU Queries - Feedback and/or suggestions wanted!

Based on what? I did test this and posted the data. The results I  
posted showed that posix_fadvise on Linux performed nearly as well on  
Linux as async I/O on Solaris on identical hardware.

More importantly it scaled with the number if drives. A 15 drive array  
gets about 15x the performance of a 1 drive array if enough read-ahead  
is done. Plus an extra boost if the input wasn't already sorted which  
presumably reflects the better i/o ordering.




-- 
greg

On 24 Oct 2008, at 04:29 AM, "Jonah H. Harris"  
<jonah.harris@gmail.com> wrote:

> On Thu, Oct 23, 2008 at 8:44 PM, Bruce Momjian <bruce@momjian.us>  
> wrote:
>> True, it is a kludge but if it gives us 95% of the benfit with 10% of
>> the code, it is a win.
>
> I'd say, optimistically, maybe 30-45% the benefit over a proper
> multi-block read using O_DIRECT.
>
> -- 
> Jonah H. Harris, Senior DBA
> myYearbook.com
>
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