Normally, when bragging, a Filipino would start his sentence with "Partida ka 
pa"  or "Wala ka sa akin" which informs the user that he'll be bragging so much 
that a tornado is coming to sweep you away so better hold on to something. Ehem 
... Yes, I can compose a long message on the iPhone, "Partida ka pa", while in 
the bus, listening to Regina Spektor with sunglasses while being tossed around 
since the driver is using the bus as his personal sports car ... hahahaha. LOL.

About the parallel algorithm. I did implement a poor man parallel 
implementation for J and its currently in production servers used in at least 3 
countries. I know I've described my implementation before where the application 
server listens to a socket/port and creates an instance of J for each client 
connection. The new J client would split the process (and essentially data) and 
does a local connection to the application server which in turns create a new 
instance of J.

The system is fast enough that it is used to supply information/processing for 
web applications. There is an overhead of course, the new connection, the new 
instance of J, the transfer of data between the client and server ... it all 
adds up that there have been instances of significant server performance 
degradation (nice way of saying my system brought the server to its knees). 
Still, running the system in "parallel" is way faster than not doing it that 
way. I remember doing the test more than 5 years ago and the performance 
difference then was staggering. 

So now I'm wondering, is a 4 cpu single core system still faster than a 2 cpu 
quad core machine? I am inclined to think that the 4 cpu single core would work 
better but I don't have metrics to back this up. I wish I can drop what I'm 
doing (building a graphical/GDI+ UI for supply chain visualization) and do some 
test. 

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf 
Of bill lam
Sent: Monday, February 15, 2010 5:40 PM
To: JChat
Subject: Re: [Jchat] [Jgeneral] Upgrade to a quad core

lun, 15 Feb 2010, Alex Rufon skribis:
> now i'm wondering, using the same parallel algorithm which one would  
> perform better? a 1 cpu quadcore machine or 4 cpu single core machine?
> 
> most of my j system running on the server are still on a 4 cpu intel  
> xeons. most of the new deployments are using the multi-core units.
> 
> i am under the impression that the single core multi cpu (4 cpu X  
> single core) setup is faster than the multi-core multi-cpu (2 cpu X  
> quad core)
> but I have no metrics to back this up. just an impression.
> 
> am i right or just batty as usual?
> 
> r/alex
> 
> 
> Sent from my iPhone
 
You can compose such a long message using iphone. ;-)

IMO it is a misconception that J (or APL) being parallel programming
language; contrary J is a vector language. J performance should be
able to improve even on single core cpu if the vector processing
capacity (simd- single instruction multiple data) of x86 cpu is
utilized.

-- 
regards,
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