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diff --git a/examples/Reactor/TP_Reactor/README b/examples/Reactor/TP_Reactor/README deleted file mode 100644 index 32fbc15aca9..00000000000 --- a/examples/Reactor/TP_Reactor/README +++ /dev/null @@ -1,86 +0,0 @@ -ACE reactor demonstration -========================= - -Martin Kolleck -Tino Riethmuller - - - -1. Introduction - -This program demonstrates what we think is a bug in the ACE library. The -affected component is the ACE_TP_Reactor. According to the documentation, the -reactor ensures that only one of the handle_*() methods of an event handler is -called at a time. Tino found this to be not true and I wrote this example -program showing the behavior. I do not exclude the possibility that we are -using the ACE library in an unintended/wrong way. So comments on the code as -well as any other remarks are welcome. - - - -2. The program - -The program consists of a client and a server. The general implementation is -taken from the example solution to exercise 4c of the ACE course. The client -will send a request to the server. This request is interpreted to be the size -of the following data. The server allocates the memory required to hold the -client's data and then sends a confirmation to the client, that it may -proceed. The the client sends the large data chunk and the server again -confirms it. - -The client runs in a loop which can be configured to run indefinitely or a -previously set amount of times. The configuration i done from the command -line. To invoke the client type: - - $ ./client size [count] - -<size> sets the size (in MiB) of the buffer sent to the server. Depending on -the systems, values between 60 and 100 have been used for testing. <count> -determines how often the buffer is sent. If left out, the clients send the -buffer until interrupted. - -The server is started without arguments. Both programs will print a dot for -each successful connection. I found this an easy and unintrusive way of showing -progress whithout flooding the console too fast. This also makes it easier to -see when an error has occurred. - - - -3. Building the program - -This example was created on a Linux box. You will need the environment -variable ACE_ROOT set up to the location where ACE is installed. It might be -possible, that the path where the ACE libraries are found, needs to be adjusted -in the Makefile. - -To compile simply type 'make' on the command prompt. - - $ make - -This will create two executable files. One for the server and one for the -client. (named respectively) - - - -4. Running the program - -The error seems to be of statistical nature. Occurring only under certain -conditions (which I am not sure of, what they are). I successfully produced -the error on the four machines given below (architecture, ACE and compiler -version). I tested the program with localhost connections, as well as over -a real network connection and could always reproduce the error. - -To detect the error I introduced a member variable to the read event handler. -This counter is initialized to zero in the constructor. When handle_input() of -the event handler is called, the counter is increased and decreased, when -handle_input() returns. Before increasing the counter, It is compared to zero -(which it should alway be, if only one invocation to handle_input() is made -at a time) and an error message is printed if it is not zero. - -To test for the error, I ran one instance of the server program and TWO -instances of the client program. The sizes of the buffers were between 60 and -100 MiB and no count was given (running until stopped) The three Linux boxes -showed the error within one minute of starting both clients. For the Windows -box I decreased the buffer size to 15 and 20 MiB (Windows does not seem to have -very performant localhost connectivity) and it took about half an -hour until the error occurred the first time. |