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diff --git a/bin/FOCUS/README b/bin/FOCUS/README deleted file mode 100644 index 14f3c804dc9..00000000000 --- a/bin/FOCUS/README +++ /dev/null @@ -1,76 +0,0 @@ - - FOCUS README - ============ - -Motivation: ----------- -Middleware is often developed as a set of frameworks that can be -extended and configured with alternative implementations of key -components, such as different types of transport protocols e.g., -TCP/IP, VME, or shared memory), event demultiplexing mechanisms -e.g., reactive-, proactive-, or thread-based), request -demultiplexing strategies (e.g., dynamic hashing, perfect -hashing, or active demuxing), and concurrency models (e.g., -thread-per-connection, thread pool, or thread-pre-request). A -particular DRE application, however, may only use a small subset -of the potential framework alternatives. As a result, general-purpose -middleware may be overly extensible, i.e., contain -unnecessary overhead for indirection and dynamic dispatching that is -not needed for use cases in a particular context. -A challenge is to develop middleware specialization -techniques that can eliminate unnecessary overhead associated with -overly extensible middleware framework implementations for certain -product variants or application-specific contexts. - -Example and Approach: --------------------- -The reactor framework in ACE allows plug and play of different -reactors such as Select, TP, Devpoll etc. The TAO middleware -implementation and applications that run atop TAO typically use -one particular implementation of the Reactor. For example, a -single-threaded application might use select_* reactors. The -Reactor framework uses the bridge pattern to transparently -invoke operations on the right reactors. When the concrete -Reactor is known, it should be possible to specialize the -framework to use the concrete reactor directly rather than use -the bridge. - -As a part of the Feature Oriented Customizer (FOCUS) tool being -,we are trying to specialize frameworks -when the concrete implementation type is known a priori. FOCUS -provides an XML based transformation engine, where the -specialization transformations are captured in XML file and a -weaver specializes the code. - -To help in this transformation process, FOCUS applies markers -within the source code. These markers are added as special -comments. For example, //@@ REACTOR_SPL_INCLUDE_FORWARD_DECL_ADD_HOOK -represents a hook where forward declarations and include files are -added by the weaver. As these markers are comments therefore should not -affect normal applications in *any* manner. Additionally, applications -that use multiple reactor implementations not be affected/do not need any -change. Currently, these specializations are targeted for TAO middleware, -where applications know the target reactor a priori and want to -leverage the specialization to improve performance. - -FOCUS Installation ------------------- -. FOCUS is written using Perl and does not require any compilation. Additionally - FOCUS does not depend on any external tools. - -Requirements ------------- -. FOCUS has been tested on Perl version 5.8.0 and uses the following Perl - packages: - -- XML::DOM package --> Perl package for processing XML DTDs - -Sample Usage: -------------- -FOCUS can be invoked from the command line in the following manner: -cmd>$ACE_ROOT/bin/FOCUS/FOCUS.pl --reactor-spl=select-st - --prefix-path=/build/arvindk/ACE_wrappers - --output-prefix=/build/arvindk/spl-files - -More Information: ------------------ -More information about FOCUS should be available from the docs directory. |