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diff --git a/docs/tutorials/010/page01.html b/docs/tutorials/010/page01.html deleted file mode 100644 index 6029dd398eb..00000000000 --- a/docs/tutorials/010/page01.html +++ /dev/null @@ -1,61 +0,0 @@ -<!-- $Id$ --> -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 010</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 010</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Passing chunks of data through an ACE_Message_Queue</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> -<P> -In an earlier tutorial we briefly introduced ACE_Message_Queue. In this -tutorial we'll go into a bit more detail. -<P> -ACE_Message_Queue is modeled after Unix System V IPC mechanisms. The basic -idea is that you put a block of data into one end of the Queue and take it -out of the other end. Your basic FIFO in other words. The SysV mechanism -works great for passing these blocks of data between processes on the same -host but it's a bit overkill for moving blocks between threads. You could -use a pipe, socket or similar mechanism but that still has more overhead than -we really want just for moving data between threads. Process-global memory -is a good technique but then you need a way to signal the "listening" threads. -The ACE_Message_Queue is a better approach: Create blocks of data and enqueue -them in one thread while another thread (or threads) dequeue and perform work. -<P> -Kirthika's Abstract: -<UL> -The Message Queue is a FIFO accessible from multiple threads. -That is, a thread puts the produced blocks of data on the message queue -to be consumed by some other thread/threads and processed. In this -tutorial, we see how effectively the Message Queue in a ACE_Task can be -used to pass data among threads in the thread pool. -(this is very similar to -<A HREF="../007/page01.html">Tutorial 7</A> - wherein we implemented a -thread-pool server).Here, actual data is passed between the threads and -also an ACE_Barrier has been used to provide synchronisation among -multiple threads. -<P> -The Message Queue consists of Message Blocks, each of which has a read -and write pointer. Using these pointers the message blocks can be -accessed for reading and writing operations. The ACE_Task::svc() method -will put the block onto the queue without bothering about the existence -of a consumer for that block. A thread from the thread pool obtains the -block from the queue, and checks to see whether the block_type is -MB_HANGUP. If so, it puts the block back on the queue for its -peers and exits. Otherwise, it reads the block and processes it before -releasing it. -<P> -This simple tutorial makes us aware of the usage and importance of the -Message Queue which could be used to our advantage especially for -multithreaded applications. -</UL> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page02.html">Continue This Tutorial</A>]</CENTER> |