OpenEuphoria

Matlab parfor equivalent

• Posted by Jerome Oct 22, 2012
• 1366 views

I have some EU code that I would like to run in parallel on mutliple cores. I've been spoiled by things like Matlab where I can use the 'parfor' command to have a for loop run in parallel. While investigating how this might work in Euphoria, I came across this post: http://openeuphoria.org/forum/113531.wc#113531 .

Out of curiosity, I wanted to see if I could come up with a very basic fix for my situation. I wrapped some of the basic pthreads commands and have something like this for EU code:

-- Allocate data to be passed to function in thread 
atom msg1 = allocate(16), msg2 = allocate(16) 
-- Pass in which chunk of the for loop to execute along with SieveBenchmark inputs 
poke4(msg1,{1,2,8192,50_000}) 
poke4(msg2,{3,4,8192,50_000}) 
 
-- Pthread code 
pthreadCreate(0,call_back(routine_id("parallelCode")),msg1) 
pthreadCreate(1,call_back(routine_id("parallelCode")),msg2) 
pthreadJoin(0)  
pthreadJoin(1) 
 
function parallelCode(atom msg) 	 
		-- Get parameter data passed in from pthread_create 
		integer start,finish,size,iterations 
		{start, finish, size, iterations} = peek4u({msg,4})  
		 
		-- For loop I wish to turn into a parfor equivalent 
		for i = start to finish do 
			SieveBenchmark({size,iterations}) 
		end for 
return 0 
end function 

As an example, I'm running the SieveBenchmark multiple times in parallel. This does the trick nicely when translated to C; I get full usage of two cores. It fails miserably when iterpreted though with machine-level exceptions. Is something along these lines easily possible with interpreted euphoria?

Thanks,
Ira