Took a look at the flyweight library.
I'm very much a beginner - so not a formal review, just a couple of
comments:
I wrote a very simple test program to try flyweight.
In essence:
vector
Hello Martin, Martin Fisher ha escrito:
Took a look at the flyweight library.
I'm very much a beginner - so not a formal review, just a couple of comments:
I wrote a very simple test program to try flyweight.
In essence:
[...]
This fails to compile with Borland Turbo C++ (internal compiler error)
This is expected as flyweight<> default factory is based on Boost.MultiIndex,
which is not supported on Borland. You might try redefining your flyweight
type as
flyweight
Under MS Visual C++ (Express 2008) it compiles ok. There is quite a performance hit over a standard vector<string> - 6s -> 80s in debug and 101s in release? From the docs I'd expected to just use copy and back_inserter?
However, the showstopper for me at present is this crashes with:
Managed Debugging Assistant 'FatalExecutionEngineError' has detected a problem in 'd:\Users\Martin\Documents\Visual Studio 2008\Projects\fly\Debug\fly.exe'.
Are you compiling in C++/CLI (CLR) mode rather than pure C++? This might be the cause of the speed penalty and the crash. I don't know how compatible the library is with managed C++'s. If you can provide me with a complete test program I'll be happy to try it myself this afternoon (in ~10 hours) and report my findings. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo
Joaquín Mª López Muñoz ha escrito:
Hello Martin,
Martin Fisher ha escrito:
Under MS Visual C++ (Express 2008) it compiles ok. There is quite a performance hit over a standard vector<string> - 6s -> 80s in debug and 101s in release? From the docs I'd expected to just use copy and back_inserter?
However, the showstopper for me at present is this crashes with:
Managed Debugging Assistant 'FatalExecutionEngineError' has detected a problem in 'd:\Users\Martin\Documents\Visual Studio 2008\Projects\fly\Debug\fly.exe'.
Are you compiling in C++/CLI (CLR) mode rather than pure C++? This might be the cause of the speed penalty and the crash. I don't know how compatible the library is with managed C++'s. If you can provide me with a complete test program I'll be happy to try it myself this afternoon (in ~10 hours) and report my findings.
You might want to take a look at a performance measuring program that is provided in the examples section: http://svn.boost.org/svn/boost/sandbox/flyweight/libs/flyweight/doc/examples... As you can see, the kind of test it performs is similar to what your program does. I've just compiled it with MSVC++ 6.0 and run it against a text file of Don Quixote (http://www.gutenberg.org/dirs/etext99/2donq10.txt, ~2 MB) and the results are (release mode): 1. simple string Time used: 7.218 s Bytes used: 44416133 2. flyweight, hashed factory Time used: 5.062 s Bytes used: 5852582 3. flyweight, hashed factory, no tracking Time used: 4.328 s Bytes used: 5750046 4. flyweight, set-based factory Time used: 5.782 s Bytes used: 5963774 5. flyweight, set-based factory, no tracking Time used: 4.953 s Bytes used: 5861238 The results are in no way similar to what you're getting, so I'm growing more suspicious the problem has to do with your using C++/CLI instead of C++. Maybe you can run the performance program yourself and compare. I'll be able to provide figures for MSVC++ 8.0 this afternoon, and, if you provide me with your test program, I will also run that. Best, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo
participants (2)
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Joaquín Mª López Muñoz -
Martin Fisher