threadpool | 易学教程

Is it possible for two ExecutorServices to share a thread pool?

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问题 I've got a collection of records to process, and the processing can be parallelized, so I've created an ExecutorService (via Executors#newCachedThreadPool()). The processing of an individual record is, itself, composed of parallelizable steps, so I'd like to use another ExecutorService . Is there an easy way to make this new one use the same underlying thread pool? Is it even desirable? Thanks. 回答1: To answer your question: no , two ExecutorService objects cannot share a thread pool. However

tornado常见的异步非堵塞写法

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【推荐】2019 Java 开发者跳槽指南.pdf(吐血整理) >>> 非堵塞和异步有什么区别？非堵塞在tornado的框架中非堵塞一般指得是网络I/O层面的socket数据接收模式(select或者epoll)，不论用哪个模式，最终程序都会收到数据并处理数据（这个数据要么被转发、要么被解析和处理）。非堵塞的弊端: 如果处理一个密集计算的请求需要花费10秒钟(就是堵塞了10秒钟)，当两个或多个请求同时到达时，只要第一个被接受处理没结束，其他全部请求都要等，并且挨个挨个等到被轮询结束。这就是单线程事件还回机制(非堵塞机制), 对堵塞零容忍, 任何一个地方堵住了还回线程，其他全部请求都被堵住。也就是说采用了非堵塞模式之后，最好不要用堵塞（常规解析数据的函数）的代码块来解析数据。异步异步的作用是将堵塞代码错开来，不放在当前接受数据的线程中处理，要么丢到rabbitmq/zeromq/activemq中交给另外一个进程去处理，要么用其他线程或进程来处理。让监听数据的这个socket收到数据后直接抛给其他程序来处理，然后立马保持监听状态，这样子程序的循环能力就非常强。再就是要提的一点，tornado本身的ioloop就采用epool/select/kqueue来完成非堵塞动作，咱们使用tornado只要把异步的代码写好就可以很好的发挥出tornado的优势了。

Android JAVA - Service return OutOfMemoryError exception after some while

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问题 I am developing my first android app. I have been created a Service class which role is to check if any new information on an external webpage. The HTTP request and service work as i should, but after a while I get these OutOfMemoryError . Are someone able to see where the Service gather all that memory? Error message 1. java.lang.OutOfMemoryError: pthread_create (stack size 16384 bytes) failed: Try again at java.lang.VMThread.create(Native Method) at java.lang.Thread.start(Thread.java:1029)

Android JAVA - Service return OutOfMemoryError exception after some while

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Windows API Thread Pool simple example

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问题 [EDIT: thanks to MSalters answer and Raymond Chen's answer to InterlockedIncrement vs EnterCriticalSection/counter++/LeaveCriticalSection, the problem is solved and the code below is working properly. This should provide an interesting simple example of Thread Pool use in Windows] I don't manage to find a simple example of the following task. My program, for example, needs to increment the values in a huge std::vector by one, so I want to do that in parallel. It needs to do that a bunch of

ASP.NET HttpContext.Current inside Task.Run

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问题 I have a following code example that is used in ASP.NET MVC application. The purpose of this code is to create "fire and forget" request for queuing some long running operation. public JsonResult SomeAction() { HttpContext ctx = HttpContext.Current; Task.Run(() => { HttpContext.Current = ctx; //Other long running code here. }); return Json("{ 'status': 'Work Queued' }"); } I know this is not a good way for handling HttpContext.Current in asynchronous code, but currently our implementation not

how are concurrent requests handled in PHP (using - threads, thread pool or child processes)

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问题 I understand that PHP supports handling multiple concurrent connections and depending on server it can be configured as mentioned in this answer How does server manages multiple connections does it forks a child process for each request or does it handle using threads or does it handles using a thread pool? The linked answer says a process is forked and then the author in comment says threads or process, which makes it confusing, if requests are served using child-processes, threads or thread

.Net How to create a custom ThreadPool shared across all the AppDomain of a process?

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问题 I made a custom ThreadPool optimized for my specific needs. However, when there are multiple AppDomains in the process, the CLR ThreadPool is able to be shared across all the AppDomains and I would like to be able to reproduce this behavior. This could be done using MarshalByRefObject and Remoting in order to create a distributed ThreadPool, but I fear that it will add unwanted overhead since the key goal of the custom thread pool is performance. Another theoretical solution would be to hack

Using JMS or ThreadPool to send email messages

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问题 I will like to know: I have a scenario. If a user adds a product to the system (I'm developing), there's a listener that sends a notification to the user's client base notifying of a new product added by the user. I've read this thread and (seeing I've never used JMS nor ThreadPool before) I was wondering whether I should use JMS or ThreadPooling. I am using Tomcat 5.5 and higher and JBoss 5 and higher (depending on company last resort) to deploy my web application. If I use JMS, do I use

Multiprocessing pool 'apply_async' only seems to call function once

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问题 I've been following the docs to try to understand multiprocessing pools. I came up with this: import time from multiprocessing import Pool def f(a): print 'f(' + str(a) + ')' return True t = time.time() pool = Pool(processes=10) result = pool.apply_async(f, (1,)) print result.get() pool.close() print ' [i] Time elapsed ' + str(time.time() - t) I'm trying to use 10 processes to evaluate the function f(a) . I've put a print statement in f . This is the output I'm getting: $ python pooltest.py f