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Question: Executing a procedure with the Task module seems slower. What am I doing wrong?

Question:Executing a procedure with the Task module seems slower. What am I doing wrong?

pake 15
parallel procedure task threads
March 14 2018
0

I'm optimizing some code and I have noticed that running a procedure within the Threads:-Task module seems to slow the procedure down. I want to use Threads:-Task to run many procedures in parallel and so finish a task faster.
I'm attaching an example of a simple "add" procedure run outside the Task module and within the Task module. As far as I know, the procedure is thread-safe, and this is shown by the similar time it takes to run 1 or 10 simultaneously.
What is going wrong?

``

> 

restart
> 

addproc := proc () local i, A; A := 0; A := add(i, i = 1 .. 1000); return A end proc
> 

ts := time[real](); for t to 1000 do addproc() end do; TA := time[real]()-ts
> 

ts := time[real](); for t to 1000 do Threads:-Task:-Start(null, Task = addproc) end do; TS := time[real]()-ts
> 

ts := time[real](); for t to 1000 do Threads:-Task:-Start(null, Tasks = [addproc, addproc, addproc, addproc, addproc, addproc, addproc, addproc, addproc, addproc]) end do; TM := time[real]()-ts
> 

TA; TS; TM

0.33e-1

  

2.049

  

2.006

 (1)
> 

TM/TA

60.78787879

 (2)

``


 

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