Executors

So this is my first time using ScheduledFuture and I admit I'm probably way over my head here. I cannot seem to get the below sample to work. Goal is simply to take two sets of actions each with it's own timeout before moving on to the next set and repeating indefinitely. static ScheduledExecutorService executor = Executors.newScheduledThreadPool(2); ScheduledFuture<?> warm = executor.scheduleWithFixedDelay(() -> { System.out.println("warmbeans"); //do more stuff here }, 0, 1000, TimeUnit.MILLISECONDS); ScheduledFuture<?> cool = executor.scheduleWithFixedDelay(() -> { System.out.println(

有三个线程分别打印A、B、C, 请用多线程编程实现，在屏幕上循环打印10次ABCABC… 这是一个比较常用的关于线程的考题，一般出现在应届生的校园招聘试卷上。 本文给出如下四种解决方法： 使用synchronized, wait和notifyAll 使用Lock 和 Condition 使用Semaphore 使用AtomicInteger 使用synchronized, wait和notifyAll /** * @author wangmengjun * */ public class SyncObj { private char letter = 'A'; public void nextLetter() { switch (letter) { case 'A': letter = 'B'; break; case 'B': letter = 'C'; break; case 'C': letter = 'A'; break; default: break; } } public char getLetter() { return letter; } } /** * @author wangmengjun * */ public class PrintLetterRunnable implements Runnable { private SyncObj syncObj;

I would make a fool out of myself if I tell you that util.concurrent APIs kicks cheetah's ass when the classes are available since 2004. However, there are some cool features which I would like to revisit. Concurrency experts, now is the time for you to close this window. All others, stay tight for the fun ride. Thou shall not forget your roots Executor is the root interface with a single execute method. Anything that implements a Runnable interface can passed as a parameter. Silly Executor, however, has no support for Callable though. Good news : ExecutorService interface, which extends

What is the low-level difference among using: ForkJoinPool = new ForkJoinPool(X); and ExecutorService ex = Executors.neWorkStealingPool(X); Where X is the desired level of parallelism i.e threads running.. According to the docs I found them similar. Also tell me which one is more appropriate and safe under any normal uses. I have 130 million entries to write into a BufferedWriter and Sort them using Unix sort by 1st column. Also let me know how many threads to keep if possible. Note: My System has 8 core processors and 32 GB RAM. Work stealing is a technique used by modern thread-pools in

I am using an ExecutorService to implement a 3-thread pool, and CountDownLatch to monitor the completion of all threads, for further processing. ExecutorService threadExecutor = Executors.newFixedThreadPool(3); CountDownLatch countDownLatch = new CountDownLatch(3); AuthorisationHistoryTask task1 = new AuthorisationHistoryTask(commonDataThread, countDownLatch ); PreAuthHistoryTask task2 = new PreAuthHistoryTask(userID,sessionID, commonDataThread, countDownLatch ); SettlementHistTask task4 = new SettlementHistTask(commonDataThread,countDownLatch); Future<Map<String, Object>> futureAuthHistory =

Spark architecture is entirely revolves around the concept of executors and cores. I would like to see practically how many executors and cores running for my spark application running in a cluster. I was trying to use below snippet in my application but no luck. val conf = new SparkConf().setAppName("ExecutorTestJob") val sc = new SparkContext(conf) conf.get("spark.executor.instances") conf.get("spark.executor.cores") Is there any way to get those values using SparkContext Object or SparkConf object etc.. Ram Ghadiyaram Scala (Programmatic way) : getExecutorStorageStatus and