I should also note that for a problem this small, a single-threaded loop over 100 strings may be just as fast or faster than launching 100 tiny short-lived threads. There is overhead to starting and quitting a parallel operation. So, having a loop inside the thread so each thread does more work before it quits could be quite efficient. Give each thread a starting point and let it check 100 perhaps.
Yes, I have seen a control in one lib called 'eureka', so the first thread to find a solution stops all other threads. The trick is to find a signal or interrupt to alert them, so all threads are not polling some variable to decide to continue.
I should also note that for a problem this small, a single-threaded loop over 100 strings may be just as fast or faster than launching 100 tiny short-lived threads. There is overhead to starting and quitting a parallel operation. So, having a loop inside the thread so each thread does more work before it quits could be quite efficient. Give each thread a starting point and let it check 100 perhaps.
Okay. Thank you for the information.
I've tried to parallelize your code. I must say, that I like it really much.
But unfortunately I have still the same behavior with the counting of the generated words. I think I have to learn more about parallelizing with OpenMP. Otherwise I'll never succeed with my small project. It's really difficult.
@Corona688: I thank you very very much for your help and for your code example.
---------- Post updated at 10:44 PM ---------- Previous update was at 10:42 PM ----------
Quote:
Originally Posted by DGPickett
Yes, I have seen a control in one lib called 'eureka', so the first thread to find a solution stops all other threads. The trick is to find a signal or interrupt to alert them, so all threads are not polling some variable to decide to continue.
Hello . Thank you for this information. Maybe this could be the solution. Okay, I have seen 'eureka' is as of OpenMP version 4.0.
But unfortunately I have still the same behavior with the counting of the generated words.
Why are you printing count? Why do you even have count? Print flag! That's what it's there for.
Finally, it's unavoidable when doing a parallel search that you may run more threads than strictly necessary. If you ran 4 simultaneous threads but found it on the very first try, that's tough luck, you ran 4 anyway.
Last edited by Corona688; 10-10-2014 at 07:08 PM..
Why are you printing count? Why do you even have count? Print flag! That's what it's there for.
Yes. Sorry, after I read your post I changed it and it works!!! Oh man, this is really amazing. I don't know how to thank you. The number of counts is absolutely correct.
I can't believe it. Since weeks I'm searching for a solution. And you gave it to me. I can't say it often enough -> thank you.
The working source code:
At least I want to post my source code. Because through the kindness of Corona688, now my code works, too.
The problem is solved. The thread can be closed. THANK YOU!!!
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