nonblocking

I'm a little confused. From the documentation : Play default thread pool - This is the default thread pool in which all application code in Play Framework is executed, excluding some iteratees code. It is an Akka dispatcher, and can be configured by configuring Akka, described below. By default, it has one thread per processor. Does it bring benefit to wrap a blocking database call in a Future , the call to the Future being itself wrapped by an async controller (returning it), in order to let the default thread pool handling other users requests? It would just move the blocking code inside

Is there a clean way to resolve a DNS query (get IP by hostname) in Java asynchronously, in non-blocking way (i.e. state machine, not 1 query = 1 thread - I'd like to run tens of thousands queries simultaneously, but not run tens of thousands of threads)? What I've found so far: Standard InetAddress.getByName() implementation is blocking and looks like standard Java libraries lack any non-blocking implementations. Resolving DNS in bulk question discusses similar problem, but the only solution found is multi-threaded approach (i.e. one thread working on only 1 query in every given moment of a

I create a FIFO, and periodically open it in read-only and non-blockingly mode from a.py: os.mkfifo(cs_cmd_fifo_file, 0777) io = os.open(fifo, os.O_RDONLY | os.O_NONBLOCK) buffer = os.read(io, BUFFER_SIZE) From b.py, open the fifo for writing: out = open(fifo, 'w') out.write('sth') Then a.py will raise an error: buffer = os.read(io, BUFFER_SIZE) OSError: [Errno 11] Resource temporarily unavailable Anyone know what's wrong? According to the manpage of read(2) : EAGAIN or EWOULDBLOCK The file descriptor fd refers to a socket and has been marked nonblocking (O_NONBLOCK), and the read would block.

From what I have been reading on The Open Group website on fcntl , open , read , and write , I get the impression that whether O_NONBLOCK is set on a file descriptor, and hence whether non-blocking I/O is used with the descriptor, should be a property of that file descriptor rather than the underlying file. Being a property of the file descriptor means, for example, that if I duplicate a file descriptor or open another descriptor to the same file, then I can use blocking I/O with one and non-blocking I/O with the other. Experimenting with a FIFO, however, it appears that it is not possible to

In Java or C# or some other languages, there are non-blocking IO facilities, e.g., for sockets. So I can give my callback functions to the non-blocking IO and once the non-blocking IO receives anything, it will call my callbacks. I am wondering how they are implemented. If I create non-blocking IO, behind the scene, does Java or C# just create background threads for them? or the OS underlying has native support for them? On Windows there is underlying OS support for non-blocking I/O, and Microsoft's CLR takes advantage of that. Other CLR implementations (mono) probably do as well, but I don't

I'm new to NIO, and I am trying to figure out how Jetty leverages NIO. My understanding of how traditional servlet containers that use Blocking IO service a request is as follows: A request arrives A thread is allocated to process the request and the servlet method ( doGet etc) is invoked Servlet method is handed an InputStream and OutputStream The servlet method reads from the InputStream and writes to the OutputStream The InputStream and OutputStream are basically tied to the respective streams of the underlying Socket What is different when an NIO connector is used? My guess is along the

I am implementing a simple server, that accepts a single connection and then uses that socket to simultaneously read and write messages from the read and write threads. What is the safe and easy way to simultaneously read and write from the same socket descriptor in c/c++ on linux? I dont need to worry about multiple threads read and writing from the same socket as there will be a single dedicated read and single dedicated write thread writing to the socket. In the above scenario, is any kind of locking required? Does the above scenario require non blocking socket? Is there any opensource