concurrent-programming

I am running a function for several sets of iterables, returning a list of all results as soon as all processes are finished. def fct(variable1, variable2): # do an operation that does not necessarily take the same amount of # time for different input variables and yields result1 and result2 return result1, result2 variables1 = [1,2,3,4] variables2 = [7,8,9,0] with ThreadPoolExecutor(max_workers = 8) as executor: future = executor.map(fct,variables1,variables2) print '[%s]' % ', '.join(map(str, future)) >>> [ (12,3) , (13,4) , (14,5) , (15,6) ] How can I print intermediary results e.g. for

fib(N)-> P1 = spawn(fun concFib:conFib/0), P2 = spawn(fun concFib:conFib/0), X=rpc(P1,N-2),Y=rpc(P2,N-1),X+Y. conFib()-> receive {Client,N} -> Client ! regfib(N) end. rpc(Pid,Request)-> case erlang:is_process_alive(Pid) of true -> begin Pid ! {self(),Request}, receive {Pid,Respond} -> Respond end end; false -> io:format("~w process is dead.",[Pid]) end. regfib(N)-> case N<2 of true -> 1; false -> regfib(N,1,1,1) end. regfib(N,N,X,_)-> X ; regfib(N,M,X,Y)-> regfib(N,M+1,X+Y,X). The idea is to divide the fib(N) process into two process one calculates fib(N-2) and the other one calc. fib(N-1)

I'm doing an academic research in trying to develop a programming tool that assists in implementing fine-grained locking functions, for concurrent programs that maintain tree-like data structures. For example, the programmer may write some functions that receive a tree root-node and modify the tree (by traversing on some routes and adding/removing nodes), and the tool will help him to find where in the code nodes should be locked and where they can be released - so the functions could be executed concurrently on the same tree. I am looking for some real-life code examples in which such fine

I want to write three concurrent go routines that sends integers to each other. Now, my code is compiled properly, however after first execution it gives error "all goroutines are asleep - deadlock!". I tried to find the error but I could not able to find any error in code logic.Can anybody help me to find the mistake with my code. My code is given below. Thanks in advance. package main import "rand" func Routine1(command12 chan int, response12 chan int, command13 chan int, response13 chan int) { for i := 0; i < 10; i++ { y := rand.Intn(10) if y%2 == 0 { command12 <- y } if y%2 != 0 {

I've read the blog, but i'm not sure whether his conclusion is correct : http://www.javacodegeeks.com/2010/09/java-best-practices-queue-battle-and.html#ixzz1seaiSLwp He said : As you can see from the provided performance results LinkedBlockingQueue achieved the best combined (adding and removing elements) performance results and should be your number one candidate for implementing producer – consumer schenarios. I wonder that, doen't it faster if i don't use lock in my code ? So why the LinkedBlockingQueue is faster than the lock-free Queue(ConcurrentLinkedQueue) ? Thanks !