c# - How to optimize and speed up this operation -

list<customer> customers = getcustomers("act"); foreach(var customer in customers) {   savecustomerdata (customer); } 

now in operation - list of customers object, in thousands save each customer object in database, 1 one. there way speed or make parallel in someway achieve performance , right result.

list<customer> customers = getcustomers("act"); task[] tasks = new task[maxnumofconcurrentsaves]; while(customers.length > 0) {      for(int = 0; < maxnumofconcurrenttasks; i++){             tasks[i] = savecustomerdata(customers[i]);             customers[i] = null;      }      customers = list.findall<customer>(customers, acust => !(acust == null));      task.awaitall(tasks) } 

ok here's whats happening (and you'll have perfect uses): while have customers in list, every 1 of them starting @ begining through max number of concurrent tasks, start task save , set customer null. then, after loop over, find customer entries in list aren't null , keep them , await tasks complete. if there's nothing left in list loop on , save process complete. savecustomerdata return task executes actual save code.

if 1 sees issues code please edit or bring attention. have not tested in capacity similar i've done works.

edit:

i have found amazing task in .net 4.5 (maybe 4 too, not sure)

list<customer> customers = getcustomers("act"); parallel.foreach(customers, (currentcustomer) => savecustomerdata(currentcustomer)) 

same thing, multithreaded in 1 line.