multithreading

问题 This question already has answers here : Setting Singleton property value in Firebase Listener (3 answers) Closed 2 years ago . public void getFoodItem( String foodNum) { dbReference=firebaseDatabase.getReference("Food"+foodNum); dbReference.addValueEventListener(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { FoodItem foodItem = dataSnapshot.getValue(FoodItem.class); Log.d("h", "Gotdata" + foodItem.getImage()); //Data can be taken from here,

问题 This question already has answers here : Setting Singleton property value in Firebase Listener (3 answers) Closed 2 years ago . public void getFoodItem( String foodNum) { dbReference=firebaseDatabase.getReference("Food"+foodNum); dbReference.addValueEventListener(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { FoodItem foodItem = dataSnapshot.getValue(FoodItem.class); Log.d("h", "Gotdata" + foodItem.getImage()); //Data can be taken from here,

问题 In order to speed up a certain list processing logic, I wrote a decorator that would 1) intercept incoming function call 2) take its input list, break it into multiple pieces 4) pass these pieces to the original function on seperate threads 5) combine output and return I thought it was a pretty neat idea, until I coded it and saw there was no change in speed! Even though I see multiple cores busy on htop, multithreaded version is actually slower than the single thread version. Does this have

问题 I've written a read-write lock using Python's concurrency primitives (I think!). Every implementation I've read on SO or elsewhere seems to use 2 locks -- one for reads, and another for writes. My implementation contains only one monitor for reads, but I may be missing something crucial -- can anyone confirm that this will work? If so, what is the benefit to using an additional write lock? This is the classic read-write lock with preference for readers (may starve writers). I use a dummy

问题 I've written a read-write lock using Python's concurrency primitives (I think!). Every implementation I've read on SO or elsewhere seems to use 2 locks -- one for reads, and another for writes. My implementation contains only one monitor for reads, but I may be missing something crucial -- can anyone confirm that this will work? If so, what is the benefit to using an additional write lock? This is the classic read-write lock with preference for readers (may starve writers). I use a dummy

问题 I have a short lock guarded section in a method (that serves the request entirely) that makes all initializations (etc. log-related). So only 1 thread can be there at time. In this section I also load system data from database if not loaded. This is naturally executed only on 1st request and it does not matter it takes time and no threads can propagate since it's done only once (by dummy request). static public void LoadAllSystemData() { SystemData newData = new SystemData(); //own type (etc.

问题 I'm trying to perform an iteration over a large set of entities to see how closely they match i initially wrote (where MatchData is a List of structs & GenerateMatch performs an operation on two entities) for (int i = 0; i < count; i++) { for (int j = i + 1; j < count; j++) { MatchData.Add(GenerateMatch(i, j)); Console.WriteLine("Stage :" + i + " ::: " + j); } } which worked fine but was pretty slow so i altered it to Parallel.For(0, count, i => { for (int j = i + 1; j < count; j++){

问题 I'm trying to perform an iteration over a large set of entities to see how closely they match i initially wrote (where MatchData is a List of structs & GenerateMatch performs an operation on two entities) for (int i = 0; i < count; i++) { for (int j = i + 1; j < count; j++) { MatchData.Add(GenerateMatch(i, j)); Console.WriteLine("Stage :" + i + " ::: " + j); } } which worked fine but was pretty slow so i altered it to Parallel.For(0, count, i => { for (int j = i + 1; j < count; j++){

问题 How can I call a method of class inside a thread? I have a simple method of class and a simple thread... How can I execute de method inside a Thread? Follow the code... #include <iostream> #include<thread> using namespace std; class Airplaine{ public: int vel = 0; void impress(){ cout << "my impress";} // meu método }; int main(){ Airplaine *av1=new Airplaine(); thread first(meu_method_impress()_here); // my method impress inside a thread first.detach(); return 0; } 回答1: To compliment the

问题 I'm writing a multithreaded socket chat. Is there any way to get the console input at a given time before the user has hit enter? Let's say I'm typing a message, and while I'm typing it, the server sends a message to me. The server's message will get printed right after the message I'm currently writing. How it looks: Me>Hey! Server>Heya! Me>How are yServer>Hello! If possible, I want to save the "How are y" string, remove it and paste it again after the server output: Me>Hey! Server>Heya!