Comments on: Counting Primes in Flash and Silverlight

By: Foxy

Foxy — Sun, 14 Mar 2010 17:49:36 +0000

I concur that the Javafx sample is unimpressive.

I intend to use the multithreading optimisation to give this a go myself.

Silverlight came out twice as fast using the example page.

Manufacturer Gigabyte Technology Co., Ltd.
Model GA-MA785GT-UD3H
Total amount of system memory 8.00 GB RAM
System type 64-bit operating system
Number of processor cores 4

By: Helge Betzinger

Helge Betzinger — Thu, 08 Oct 2009 15:32:46 +0000

Update: with silverlight3 its even more impressive. Within Firefox 3 we have:
Flash10: Number of primes up to: 1000000 is 78498, counted in 1.247 secs.
Silverlight3: Number of primes up to: 1000000 is 78498, counted in 0.22 secs.
Adobe should take care for the performance of its JIT.

By: vodacoder

vodacoder — Sun, 07 Jun 2009 23:57:03 +0000

the javafx sample isn’t very impressive since it won’t even come up….seems like it takes forever to load any of those javafx examples….not even in the same class as flex and silverlight.

By: Aditya

Aditya — Thu, 29 Jan 2009 17:08:58 +0000

Have you try it in JavaFX? Here is the Link:

http://javafx.com/samples/PrimeFactors/index.html

Try it! It really fast! Fastest than AdobeFlash, Microsoft Silverlight and JavaScript.

By: james

james — Sat, 20 Dec 2008 16:50:05 +0000

for (i=3; i l2) { l++; l2=l*l; }


		numprimes++;

for (j = 3; j < l+1; j+=2) { if (i / j == 0) { numprimes--; break; } } }

By: james

james — Sat, 20 Dec 2008 16:49:26 +0000

whoops code got truncated, the loop should read:

for (i=3; il2) { l++; l2=l*l; }


		numprimes++;

for (j = 3; j < l+1; j+=2) { if (i / j == 0) { numprimes--; break; } } }

By: james

james — Sat, 20 Dec 2008 16:41:57 +0000

Tweaking the code slightly to optimize unnecessary floating-point and calculations, I get (on my crappy little laptop):

C/x86 ~1s
C#/CLR ~1s
JS/V8 ~1.5s
AS3/AVM2 ~3s

This benchmark on an x86 will generally end up with an inner loop of:

idiv eax,ecx
test edx,edx

I havent looked up the cycle counts, but I wouldn’t expect modern CPU to heavily optimize integer division – as its pretty much a rare edge case.

Code (C#/C flavor):

int primes(int n)
{
int numprimes=1;
int l=2;
int l2=l*l;
int i;
int j;

for (i=3; il2)
{
l++;
l2=l*l;
}

numprimes++;

for (j = 3; j < l+1; j+=2)
{
if (i % j == 0)
{
numprimes–;
break;
}
}
}
return numprimes;
}

By: Ryan

Ryan — Fri, 14 Nov 2008 18:16:00 +0000

I am actually looking for engineers interested in working on a new UI Platform product similar to Silverlight. Anyone interested?

-Ryan Phillips
engineerfinder@live.com

By: Bart Czernicki

Bart Czernicki — Wed, 10 Sep 2008 01:42:21 +0000

I took the code and wrote a detailed article on improving it with multithreading inside Silverlight.

http://www.silverlighthack.com/post/2008/09/07/Silverlight-MultiThreading-with-a-Computational-Process

I don’t think that Flash/Flex have true multithreading…so this makes Silverlight even faster! On my machine I got about a 100% improvement in speed.

By: Yitzchok

Yitzchok — Wed, 03 Sep 2008 04:38:20 +0000

Google Chrome JavaScript (V8)

Number of primes up to: 1000000 is 78498, counted in 3.216 secs.