synchronization

问题 What does this java code mean? Will it gain lock on all objects of MyClass ? synchronized(MyClass.class) { //is all objects of MyClass are thread-safe now ?? } And how the above code differs from this one: synchronized(this) { //is all objects of MyClass are thread-safe now ?? } 回答1: The snippet synchronized(X.class) uses the class instance as a monitor. As there is only one class instance (the object representing the class metadata at runtime) one thread can be in this block. With

问题 Is it safe to use __syncthreads() in a block where I have purposefully dropped threads using return ? The documentation states that __syncthreads() must be called by every thread in the block or else it will lead to a deadlock, but in practice I have never experienced such behavior. Sample code: __global__ void kernel(float* data, size_t size) { // Drop excess threads if user put too many in kernel call. // After the return, there are `size` active threads. if (threadIdx.x >= size) { return;

问题 Numba lacks the cuda-C command gridsync() so there is not a canned method for syncing across an entire grid. Only block level syncs is available. If cudaKernal1 is a very fast execution time then the following code would run 1000x faster for i in range(10000): X = X + cudaKernel1[(100,100),(32,32)] (X) by putting the loop into the same kernel, to avoid the gpu kernel setup time. But you can't because you require all of the grid to finish before the next iteration can start, and there is no

问题 Disclaimer: My C# isn't even close to as good as my C++ I am trying to learn how to do async sockets in C# in order to write a test app for a component of mine. My former attempts using TcpClient ended in failure and you can read the outstanding questions on that here: TcpClient.NetworkStream Async operations - Canceling / Disconnect Detect errors with NetworkStream.WriteAsync Since, I could not get that working, I tried using Socket.BeginX and Socket.EndX instead. I got much further along.

问题 public class ObjectA { private void foo() { MutableObject mo = new MutableObject(); Runnable objectB = new ObjectB(mo); new Thread(objectB).start(); } } public class ObjectB implements Runnable { private MutableObject mo; public ObjectB(MutableObject mo) { this.mo = mo; } public void run() { //read some field from mo } } As you can see from the code sample above, I pass a mutable object to a class that implements Runnable and will use the mutable object in another thread. This is dangerous

问题 The simplest solution is perhaps some await after adding some promise pattern, or reusing... I not see how to reuse the Promise, that I suppose it already exists, into the method csv-parse.readFileSync() , or the method parse() , illustrated below. Another solution is to add more promises and some async/await : the whole LOAD block can be a function... But I also not see where put the awaits. 'use strict'; const fs = require('fs') const path = require('path') // CONFIGS: const cf_cover

问题 I have a single public variable in a class bool toSwitch = false; Func_Thread1() { if(toSwitch) { ..... .... toSwitch = false; } } and Func_Thread2() { toSwitch = true; } The Func_Thread1 will get called frequently(2 seconds once) and during certain interval Func_Thread2 will get called(1 minute once) and change the global variable to true. So at the next Func_Thread1 call the if condition will become true. Does the toSwitch needs synchronization as it can read and modified by different

问题 I've got a client who has a very large internal system using Access, which is used internally to handle virtually all company data. They want a web front-end to the customer data in that database, and would be running on a different server. Given the limitations on Access, the front-end would likely use MySQL. Which leaves the issue of synchronizing the data. It doesn't need to be to-the-second, even daily would be fine, but I'm really unsure of a good means of doing this. Given the scope of

问题 Let's say i have a class Foo and it has a static member variable named Count ( type is integer). This variable was used in a multithreaded application and i was using lock synchronization mechanism before doing any read/write to this variable. As I am reading this article Volatile I am getting the impression that i can remove all those locks around this variable and just use volatile keyword at declaration of this variable. That should take care of all the synchnronization related stuff. Is

问题 We are some Devs working on an internal TFS-Repository. This TFS can only be accessed from within out network. But we also have a test-lab which wasn't meant to, but ended up in being a development environment. Because we do not have any access to our company's TFS we used Microsofts tfs (visualstudio.com) instead. We do not have the chance to change ANYTHING in our network-structure. So stuff like "just allow your test-machines to access your internal TFS would be of no help) Some of our DEV