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From: aminer <aminer@toto.net>
Newsgroups: comp.programming.threads,comp.programming
Subject: Scalability...
Date: Wed, 09 Oct 2013 18:19:31 -0700
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Hello,

So if you have understood my ideas and my arguments against the Amdahl's 
equation, i have proved to you that the Amdahl's equation gives you the 
scalability that you will have in an IDEAL CONTENTION SCENARIO , but if 
you have less contention it will scale much better, and in a none 
contention scenario it will have a perfect scalability, so if you have a 
small serial part
let say of S = 0.1% so the Amdahl's equation says that your program will
scale to a maximum of 10, but that's false , it can scale much more
than that if you introduce randomness in the Parallel part to avoid
the ideal contention scenario, something like 
wait(random(something_like_the+time_of_your_bigger_locked_region)) or 
something like that and this will scale your application to much more 
than 10X, so the very important part is to introduce an optimal 
randomness of a more optimal wait , but you don't have to use sleep() 
for that,
just to loop around a pause asm instruction for example and this will give
you better scalability than 10X.


Thank you,
Amine Moulay Ramdane.