visual studio 2010 - TPL Task return values -

i have application face recognition system received camera frames around 30 : 50 frame/second depending on camera type , each frame have anther function persons on , each persons in person in current frame check if person exist in database or not database records it’s around 100,000 records , steps made ever frame

i rewrite previous question simple c# statement more clear

// frame camera can consider it's inside loop (int frame = 1; frame < 50; frame++) {     // each fram person insied frame     // list<persons>     foreach (var perosn in allpersons_inframe)     {             // each person need check          //against database recored         foreach (var recored in database)         {             // perosn exist in database             // give me person id         }     } } 

till application working without problems have anther dea make task more simple , take small time comparing current time taken .i need used parallel programming "tpl" how : need divide database record 5 part each part around 20,000 record , process 5 parts in parallel way , wait till 5 part finished , check if part have result main final result

but don’t know how implant idea hope question clear

so please if 1 has idea me implement idea grateful him

i didn't test, hope helps.

// define logic here. func<ienumerable<person>, string> yourlogichere = null; // define way compare task result here. func<ienumerable<task<string>>, string> dealwiththetaskresultshere = null; collection<person> persons = new collection<person>(); task<string> maintask = new task<string>(tmpobj =>     {         var tmppersons = tmpobj collection<person>;         if (tmppersons != null)         {             int interval = (int)math.ceiling(tmppersons.count / 5d);             int index = 0;             collection<task<string>> subtasks = new collection<task<string>>();             while (index < tmppersons.count)             {                 task<string> subtask = new task<string>(                     (tmpsubpersons) => { return yourlogichere((ienumerable<person>)tmpsubpersons); },                     tmppersons.skip(index).take(interval).toarray(), taskcreationoptions.attachedtoparent);                 index += interval;                 subtasks.add(subtask);             }              foreach (var subtask in subtasks)             {                 subtask.start();             }              foreach (var subtask in subtasks)             {                 subtask.wait();             }              return dealwiththetaskresultshere(subtasks);         }         else return string.empty;     }, persons);  maintask.start(); maintask.wait(); return maintask.result;