Re: Straightforward changes for increased SMP scalability

Gregory Stark wrote:
> "Joshua D. Drake" <jd@commandprompt.com> writes:
> 
>> +1 on the idea (I can speak to the technical side). What I can say is that it
>> is pretty much known that after 8 cores we slow down. Although 8.2 is better
>> than any other release in this regard.
> 
> Wait, what benchmarks have you seen where we slow down? 

The production type. :)

Hmm maybe that is a bad way to put it. I am not saying we slow down like 
we move slower than before. I mean per processor performance goes down. 
If I have 4 Cores things rock and roll. If I have 8 cores (and obvious 
sufficient workload) things rock and roll louder than 4 cores.

If I have 16 cores, things are still really loud but I start to not be 
able to tell the difference. The percentage of improvement is much lower.

E.g, 16 cores works and PostgreSQL work great, but it is not nearly as 
fantastic with 16 cores as 8 cores (in terms percentage gain).



Sincerely,

Joshua D. Drake


> 


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