race-condition

问题 In order to debug some concurrency issues, I am in the process of switching part of my code from working on a regular Golang map to working on a sync.Map. However, when I try to run my new code, I am encountering two errors that I'm not sure how to debug. The original code block: sync_mutex.Lock() if _, ok := the_map[cur_h]; ok { the_map[cur_h] = append(the_map[cur_h], cur_id) } else { value := []int{cur_id} the_map[cur_h] = value } sync_mutex.Unlock() The new code block: if _, ok := sync_map

问题 I'm wondering if it is safe to use rsync to hotbackup a git server (The /home/git folder containing multiple repositories). I'm assuming that this could introduce race conditions, but perhaps git commit is an atomic operation such that rsync either sees the files as they are before the commit or after the commit but not somewhere inbetween. I'll provide an example as well just to make sure I'm illustrating this properly. Suppose file A and file B are being committed to one of the repositories

问题 I'm looking at using PipelineDB for analytics. For data warehousing I want to append all new data to a file, and tail -F it into psql like the examples on the website. I have multiple data sources, so to get deterministic results, I'd like to append them all to the same input file, where they'll stay in the same order. Is there a simple, idiomatic way of avoiding race conditions? Something like a single-file server I can pipe data to? Edit: Actually, a race condition is exactly what I want .

问题 Perhaps it's my naiveté, perhaps my paranoia, but I think I'm looking for a solution to a race-condition issue that seems like it should be so common there'd be floods of solutions and I'd've found one by now... but I haven't. The simplistic scenario is I have a process that's supposed to grab any records where there are more than one of a certain type. I'd like to make the system/process(es) thread-/multiprocessing-/reentrant-/buzzword-of-the-day-safe; if the same process gets started and

问题 Basic Setup I use NSTask to run a process that optimizes images. This process writes output data to stdout . I use the readabilityHandler property of NSTask to capture that data. Here is the abbreviated setup: NSTask *task = [[NSTask alloc] init]; [task setArguments:arguments]; // arguments defined above NSPipe *errorPipe = [NSPipe pipe]; [task setStandardError:errorPipe]; NSFileHandle *errorFileHandle = [errorPipe fileHandleForReading]; NSPipe *outputPipe = [NSPipe pipe]; [task

问题 When multiple processors are working, the processes are working concurrently. Race condition happens when multiple threads accessing some common data area, one may overwrite the other value. So, if it is a single processor and single core environment, can it prevent the race condition from happening? Help me clarify this confusion, Thank you. 回答1: A race condition could happen in Single processor environment. As per Wiki Race Condition occurs when output is dependent on the sequence or timing

问题 I'm running the following code to start my threads, but they don't start as intended. For some reason, some of the threads start with the same objects (and some don't even start). If I try to debug, they start just fine (extra delay added by me clicking F10 to step through the code). These are the functions in my forms app: private void startWorkerThreads() { int numThreads = config.getAllItems().Count; int i = 0; foreach (ConfigurationItem tmpItem in config.getAllItems()) { i++; var t = new

问题 I recently discovered the racecheck tool of cuda-memcheck , available in CUDA 5.0 ( cuda-memcheck --tool racecheck , see the NVIDIA doc). This tool can detect race conditions with shared memory in a CUDA kernel. In debug mode, this tool does not detect anything, which is apparently normal. However, in release mode (-O3), I get errors depending on the parameters of the problem. Here is an error example (initialization of shared memory on line 22, assignment on line 119): ========= ERROR:

问题 I'd like to use POSIX semaphores to manage atomic get and put from a file representing a queue. I want the flexibility of having something named in the filesystem, so that completely unrelated processes can share a queue. I think this plan rules out pthreads. The named posix semaphores are great for putting something in the filesystem that any process can see, but I can't find the standard CondWait primitive: ... decide we have to wait .... CondWait(sem, cond); When CondWait is called by a

问题 Let's assume I'm using a Background Worker and I've the following methods: private void bw_DoWork(object sender, DoWorkEventArgs e) { finalData = MyWork(sender as BackgroundWorker, e); } private void bw_ProgressChanged(object sender, ProgressChangedEventArgs e) { int i = e.ProgressPercentage; // Missused for i Debug.Print("BW Progress Changed Begin, i: " + i + ", ThreadId: " + Thread.CurrentThread.ManagedThreadId); // I use this to update a table and an XY-Plot, so that the user can see the