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diff --git a/docs/tutorials/013/page01.html b/docs/tutorials/013/page01.html deleted file mode 100644 index f222eb01202..00000000000 --- a/docs/tutorials/013/page01.html +++ /dev/null @@ -1,63 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 013</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 013</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Multiple thread pools</FONT></B></CENTER> -<P> -<HR WIDTH="100%"> -<P> -My intent with this tutorial was to derive from ACE_Data_Block instead -of ACE_Message_Block so that we could leverage the reference counting -nature of that object. -<P> -Along the way, I sort of got distracted... What I ended up with is a -poor excuse for ACE_Stream that implements a simple state machine. -<P> -The application is built around a thread pool where the pool's svc() -method takes work units from the message queue for processing. As -each unit is taken from the queue, the process() method is invoked to -do some work. The twist is that after processing the message, we -enqueue it into another thread pool to do more work. This continues -through a chain of thread pools until the last where the unit's fini() -method is called for finishing up any outstanding work. -<P> -The chain of thread pools is uni-directional using a singly-linked -list of Task derivatives. Each pool has the same number of tasks in -order to keep things simple. -<P> -Kirthika's abstract: -<UL> -In this tutorial, a singly linked list of thread-pools, each of which is -a subtask and which acts as the finite state machine node, is used to -simulate a finite state machine. -<P> -A task is created with a number of subtasks. Once the message block is -obtained from the queue, it is verified to see whether a task has a -subtask. If so, it is forwarded to the subtask. Thus the mesage -traverses over the whole list. As a safety measure for destroying the -block after it goes through the whole list, an effective and simple -Memory Leak Detector has been implemented. It is a counter which -increments when the object where it resides is created and decrements on -its deletion. -<P> -Another optimisation from the previous tutorials on Message Queues, is -the bundling of the Data block within the Message Block. The Data block -provides reference counting, so duplication of data is avoided. It is -deleted only when its reference count drops to zero. Now updating -this count between threads call for synchronisation and in comes the -ACE_Mutex, a lock which takes care that the counting is thread-safe. -<P> -Although the example isn't a full-fledged Finite State Machine, -i.e. it has to be tweaked to be able to jump states on different inputs, -it definitely proves to be a great lesson and introduces us to quite a -few new ACE classes and the ways they can be mixed and matched to -produce the end-system desired. -</ul> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page02.html">Continue This Tutorial</A>]</CENTER> |