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diff --git a/docs/tutorials/007/page01.html b/docs/tutorials/007/page01.html deleted file mode 100644 index a1cd7ceac79..00000000000 --- a/docs/tutorials/007/page01.html +++ /dev/null @@ -1,82 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.04 [en] (X11; I; Linux 2.0.32 i486) [Netscape]"> - <META NAME="Author" CONTENT="James CE Johnson"> - <META NAME="Description" CONTENT="A first step towards using ACE productively"> - <TITLE>ACE Tutorial 007</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 007</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Creating a thread-pool server</FONT></B></CENTER> -<HR> - - - -<P>In this tutorial, we're going to extend Tutorial 6 to add a third concurrency -strategy: thread-pool. Like Tutorial 6 did to Tutorial 5, we're -going to keep the existing strategies that we've already created and add -this one in as a "bonus". As you'll see, our basic objects will change -but not by a whole lot. To accomplish this, we'll introduce one new -major object that helps to abstract the thread pool concept. -<P> -Some folks have noted that this tutorial is a bit confusing if you -don't first know about ACE_Task. My advice is to give it all a good -read a couple of times. If you're still having problems, take a look -at the ACE_Task tests in $ACE_ROOT/tests or examples in $ACE_ROOT/examples. -<P> -Kirthika's Abstract: -<UL> -In this multithreaded server, the Client_Acceptor has the additional -strategy of managing a thread pool. This helps when two clients don't -want to share the same resources or when different clients -need to run in different priority threads. We could then pool all the -same priority clients into one thread-pool. The thread_pool class is a -new addition used to implement this strategy. It inherits from ACE_Task -with ACE_MT_SYNCH parameter which takes care of syncronization issues -amongst multiple threads. -<P> -ACE_Task follows the Active Object pattern and executes the methods on -the task object in a new thread of execution, i.e it decouples the -execution of a method from its invocation. An ACE_Task has an underlying -thread (or pool of threads) and a Message_Queue which is the only means -of communication among tasks. A Message_Queue consists of -Message_Blocks. -<P> -The Client_Acceptor is registered with the reactor waiting for -connection requests. -On some activity, the reactor calls the handle_input() method on the -Acceptor. The Client_Handler of the Acceptor (for the thread-pool -strategy) unregisters itself from the reactor and -enqueues itself in the Message_Queue of the thread-pool waiting for -svc() to call handle_input() on it. It would then process the data in -its new thread of execution. The ACE_MT_SYNCH option facilitates access -of the Mesage_Blocks across different Message_Queues (here from the main -thread to the one in the thread pool). -<P> -The thread_pool class derives from the ACE_Task class. Its svc() method -dequeues the threads in the Message_Queue and calls handle_input() on -them. The idle threads can take work from the queue while the other -threads are working. It also uses ACE_Atomic_Op as a counter for active -threads in the pool. Also, the ACE_Guard class has been used to provide -thread-safe counter-incrementation and destruction of the Message_Blocks -of the thread-pool. This class guards the critical section region by -acquiring the mutex lock on creation and releasing it as soon as it goes -out of scope. -<P> -Note: a sleep period before all the threads in the pool exit is -necessary for complete destruction of the thread pool. -<P> -This tutorial gives us a flavour of implementing a server with a -thread-pool strategy and how it can be managed using the ACE_Task class, -which provides an OO approach to thread-creation and implementation. -</UL> -<font size=-1>* The additions to this tutorial make use of -ACE_Message_Queue which is discussed in depth in -<A HREF="../010/page01.html">Tutorial 10</A>. Feel free to read ahead -if you get lost in the message queue stuff. -</font> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page02.html">Continue This Tutorial</A>]</CENTER> |